Mermail Guide

I -  Introduction

II - Mariners and Maidens of the Forgotten Sea (Mermails)

III -Weapons of the Deep (Mermail Spells and Traps)

IV -Atlantean Ammunition (Atlanteans)

V - Aquatic Allies (Monster Techs)

VI -Exotic Weaponry (Spell/Trap Techs)




Mermails are a WATER-based archetype introduced in Abyss Rising that focus on generating advantage via discarding, summoning monsters that can disrupt the opponent, or bringing out huge beaters straight from the deck, hand or graveyard. The maidens themselves are all Aqua, the mermen are all Fish, while the big Lv7s are Sea-Serpents, bar Mermail Abyssteus and Mermail Abyssbalaen. So as you can see, Mermails have a wide variety of Types, but seeing how most WATER-support cards affect all three of the main WATER types, that shouldn't be a problem.

Before we get into the guide proper, it should be known that our most common allies are Atlanteans. See, many Mermail monsters require a cost, either for discarding or for tribute, which in turn facilitates the Atlanteans, who need to be used as a cost for a WATER monster to activate their effect. While it's certainly possible to form a pure Mermail deck, or one without Atlanteans, we highly advise against it. But that's not to say that the two are bound for life; there exist many an Atlantean deck without Mermails, hence why they have their own guide and we have ours. With that said, let's begin.




First, let's talk about our main stars: the Mermails themselves.



Mermail Abysslinde

Level 3 / Aqua / Water
1500 / 1200
If this card on the field is destroyed and sent to the Graveyard: You can Special Summon 1 "Mermail" monster from your Deck, except for "Mermail Abysslinde". The effect of "Mermail Abysslinde" can only be activated once per turn.

The floater of the Deck. She's the main target for Abyss-sphere because upon her destruction she will get you another Mermail. Note that there's no level restriction, allowing for easy Megalo/Leed summons straight from the deck. This card makes Torrential an even more amazing card. Pike can search her from the deck and Sturge/Salvage can recycle her. She's a little on the slow side, however, since she has to be destroyed to trigger her effect.
Run 2-3.



Mermail Abyssgunde

Level 3 / Aqua / Water
1400 / 800
If this card is discarded from your hand to the Graveyard: You can Special Summon 1 "Mermail" monster from your Graveyard, except "Mermail Abyssgunde". Only one "Mermail Abyssgunde" can have its effect activated per turn.

A themed Monster Reborn, Gunde mitigates discarding costs by summoning a Mermail from your graveyard, allowing for easy Mermonster summons and combos with Sturge and Pike. She's also a Salvage target. Searchable by Pike. Since she can summon our Level 7 bosses, she can facilitate Rank 7 plays. Even more shenanigans with Tidal, but we'll get to that later. Warning: If Gunde ends up in Chain Link 2, then a Special Summoned Pike/Sturge/Abyssdine will miss their timing for any of their effects. Discarding Gunde + Atlantean for a Megalo summon mandatorily puts her at Chain Link 2. Also, if she is discarded on your opponent's turn by something like Dark World Dealings, then she will also be put into Chain Link 2 assuming opponent has a monster that is triggered from discard (like Dark Worlds). She herself will never miss the timing though, so remember that.
Run 1-3.



Mermail Abysshilde

Level 3 / Aqua / Water
1400 / 800
If this card is sent to the Graveyard: You can Special Summon 1 "Mermail" monster from your Hand, except "Mermail Abysshilde". Only one "Mermail Abysshilde" can have its effect activated per turn.

This card is similar to Dandylion in that she doesn’t care how she ends up in your graveyard, as long as she gets there. Theoretically she's an easy way to summon Megalo, Leed and the other Mermails with ease, but at the cost of depleting your hand. Searchable by Pike and also recyclable via Salvage and Sturge. Special summoning from grave is better advantage-wise, so she isn't an optimal choice.
Run 0-1.



Mermail Abyssdine

Level 3/ Aqua / Water
1000 / 200
When this card is added from your Deck or Graveyard to your hand by a card effect: You can Special Summon this card from your hand. You must control a "Mermail" monster to activate and to resolve this effect. When this card is Special Summoned by the effect of a "Mermail" monster: You can target 1 Level 3 or lower "Mermail" monster in your Graveyard; Special Summon that target. You can only use 1 "Mermail Abyssdine" effect per turn, and only once that turn.

Pay close attention to her "only one effect per turn" clause. Kind of restricts you, but by no means does it ruin her synergy. Pike/Teus/Sturge/Salvage activate her "SS from Hand" effect while Linde/Gunde/Hilde/Trite activate her "SS Lv3 Mermail from Grave" effect. Speeds up Rank 3 plays and Linde->Dine gives you defense on your opponent's turn (Dine will SS the destroyed Linde). Whether she's for you depends entirely on whether you can afford to take your time and prepare large Xyz plays. She's prone to dead draw, so beware.
Run 0-1.



Mermail Abyssocea

Level 3 / Aqua / Water
1100 / 1900
You can target 1 "Mermail" monster you control; Special Summon any number of Level 4 or lower "Mermail" monsters from your Deck whose combined Levels are less than or equal to the Level of that monster, then send that monster to the Graveyard. You can only use the effect of "Mermail Abyssocea" once per turn.

This one has quite a lot of combos to it. Speeds up XYZ plays, namely Rank 3 plays. Trade your Lv7 Mermonster for 2 Lv3 Mermails or a Lv3 + Lv4 Mermail. Her + 2 Lv3 Mermails = Instant Trite or Zenmaines + Linde. Please note that she will make Pike/Sturge/Dine miss timing, because their summon wasn't the last thing to happen. She's still a decent Level 3 choice with nice defense.
Run 0-1.



Mermail Abysspike

Level 4 / Fish / Water
1600 / 800
When this card is Normal or Special Summoned: You can discard 1 WATER monster to the Graveyard; add 1 Level 3 WATER monster from your Deck to your hand. The effect of "Mermail Abysspike" can only be activated once per turn.

The Stratos of the deck, alongside Dragoons. Not too threatening as a foot soldier, but his effect is what makes the Deck so great. Easily activate his effect on your opponent's turn with a (Sphere->)Linde play. Combine with Atlanteans to have them end their turn -1'd or with you searching. Also comboes nicely with Gunde. Searches Marksman, Linde, Gunde, Hilde, Dine (and activates her), Undine, Archer, or any other Lv3 WATER you run. Searchable with Abyssteus.
Run 2-3.



Mermail Abyssturge

Level 4 / Fish / Water
1700 / 1100
When this card is Normal or Special Summoned: You can discard 1 WATER monster; add 1 Level 3 or lower WATER monster from your Graveyard to your hand. The effect of "Mermail Abyssturge" can only be activated once per turn.

Virtually a reverse of Pike, this guy is a walking Monster Reincarnation. Great for reusing Atlanteans, our maidens, and even Diva if you run her, while getting advantage from whatever monster you discarded. Early in the game this card can be quite dead because of the lack of any targets in your graveyard, so be wary when running him.
Run 0-1.



Mermail Abysslung

Level 4 / Fish / Water
1200 / 1800
Your opponent cannot target other face-up WATER monsters you control for an attack. All face-up WATER monsters on the field gain 300 ATK, except this card.

You know that card every archetype gets that isn’t direct support and most of the time sucks? Well, here’s the Mermail equivalent to that.
Run 0.



Mermail Abyssnose

Level 4 / Fish / Water
1500 / 1500
When this card destroys an opponent's monster by battle and sends it to the Graveyard: You can discard 1 WATER monster to the Graveyard; Special Summon 1 "Mermail" monster from your Deck in face-up Defense Position. You can only use the effect of "Mermail Abyssnose" once per turn.

Mermail's version of Blackwing - Shura the Blue Flame. He tries to emulate his brothers Pike and Sturge, but winds up being unreliable due to his low ATK. And honestly, Linde and even Ocea do his job better.
Run 0



Mermail Abyssmander

Level 4 / Fish / Water
100 / 2000
You can banish this card from your Graveyard to activate 1 of these effects:
* Increase the Level of all "Mermail" monsters you currently control by 1.
* Increase the Level of all "Mermail" monsters you currently control by 2.

Our first Mermail TCG Exclusive, from Abyss Rising. If you're the kind of person who like to churn out XYZs with your Mermails, this guys lets you run a spectrum of Ranks 3 through Rank 9. In its own dedicated build, this guy brings the thunder.
Run 0-2.



Mermail Abyssmegalo

Level 7 / Sea-Serpent/ Water
2400 / 1900
You can discard 2 other WATER monsters to the Graveyard; Special Summon this card from your hand. When you do: You can add 1 "Abyss-" Spell/Trap Card from your Deck to your hand. You can Tribute 1 other face-up Attack Position WATER monster; this card can make a second attack during each Battle Phase this turn.

The main boss of the Deck, without question. Abyssmegalo will activate Abysshilde, Abyssgunde, and the Atlanteans with ease. His SS cost might seem steep, but combine it with those cards and you'll break even easily. Its Blade Armor Ninja tributing effect also triggers Atlanteans, granting you a Pop/Search and a Double Attack. Don't forget he can search an "Abyss-" card, nabbing you a Sphere upon summon. Searchable by Dragoons as well. And did we mention that him + Deep Sea Diva is an OTK? This card is THE must have for any Mermail deck. He sets up damn near everything. Be aware though that late game he isn't the best topdeck.
Run 2-3.



Mermail Abyssleed

Level 7 / Sea-Serpent/ Water
2700 / 1000
You can discard 3 other WATER monsters from your hand to your Graveyard; Special Summon this card from your hand. When Special Summoned this way: You can target 1 "Abyss" Spell/Trap Card in your Graveyard; add that target to your hand. You can Release 1 other face-up Attack Position "Mermail" monster you control; send 1 random card from your opponent's hand to the Graveyard. This effect of "Mermail Abyssleed" can only be activated once per turn.

You'll probably notice that "Discard 3" in his effect. BUT DON'T LOOK AWAY! Leed isn't without his perks. Right off the bat, he has 2700 ATK. That's 300 more than Megalo, which might not seem like much. However, that 300 boost is enough to differentiate and overpower many common beaters. Sphere/Linde into Leed and instant pressure on your opponent. His hand-discarding effect isn't too bad either, but lacks Atlantean synergy. You'd rather SS him from the Deck or from the Grave instead of using his own SS effect, but on the offchance you pull it off, getting back Sphere is always great.
Run 0-1. You don't want to draw him.



Mermail Abyssteus

Level 7 / Aqua / Water
1700 / 2400
You can discard 1 other WATER monster to the Graveyard; Special Summon this card from your hand. When you do: Add 1 Level 4 or lower "Mermail" monster from your Deck to your hand. You can only use this effect of "Mermail Abyssteus" once per turn.

We wanted a good TCG Exclusive, and man did Konami deliver. He's a sea monster, and he's Level 7, so you'd think he'd be with the other Sea-Serpents. But nope; he's an Aqua. He's that one guy who can't be searched out with Dragoons, but in Return you can now search your Abysspikes and Abyssturges (and remaining non-Lv7 Mermails). Its searching power is incredibly handy. Easy Lv7 to bring out, and he makes a hand full of Mermonsters look like a good thing. Abyssteus alone gave birth to the Mono Mermail build, because Rank 7s became incredibly easy upon his release. This is the guy you want to be running in any Mermail build.
Run 3.



Mermail Abyssbalaen

Level 7 / Aqua / Water
2500 / 2000
You can discard 4 other "Mermail" monsters to the Graveyard; Special Summon this card from your hand. When you do: Target cards your opponent controls, up to the number of "Mermail" monsters in your Graveyard (if possible); this card gains 500 ATK, and if it does, destroy those targets (if any). You can Tribute 1 other face-up Attack Position "Mermail" monster; this card gains the following effect this turn.
● At the start of the Damage Step, if this card battles a Defense Position monster: Destroy that monster.

Also known as "Mermail Fail Whale", "Sea Thor", or "that ****** Mermail from LTGY".
There are simply too many things wrong with this card. Its cost is so steep and really situational to boot. It has a really subpar secondary effect, and it barely has the stats to even consider a Leed-esque beater spot. If you SOMEHOW get him out then your opponent will be left with little to no field left, but a Torrential or Bottomless laughs at it so hard. You're better off avoiding this guy. He has neat art though.
Run 0.

We're fortunate enough to have 2 Xyz monsters as well:



Mermail Abyssgaios

Rank 7 / Sea Serpent / Water
2800 / 1600
2 Level 7 WATER monsters
While this face-up card has any Xyz Material, Level 5 or higher monsters cannot attack. Once per turn, during either player's turn: You can detach 1 Xyz Material from this card; negate the effects of all monsters your opponent controls whose ATK is lower than this card's ATK, until the End Phase.

Poseidon himself, coming to wreck face. He's a Rank 7, which is perfect for us. This monstrosity negates almost all relevant effect monsters out there and it has the ATK to back it up. With a pseudo Gravity Bind effect and the ability to negate the effects of everything, this beast is something our enemies are going to have to keep on check. Its summoning requirements aren’t hard to achieve either; any 2 Mermonsters can make him, with Abyssteus and Tidal making it even easier.
Run 1-2. It depends on how much the meta calls for his necessity.



Mermail Abysstrite

Rank 3 / Sea Serpent / Water
1600 / 2800
3 Level 3 monsters
When 1 "Mermail" monster you control is targeted by your opponent's Spell/Trap Effect or for an attack: You can detach 1 Xyz Material from this card; switch that target to this card, if it is an Appropriate target. When this card is destroyed by a card effect and sent to the Graveyard: You can target 1 "Mermail" monster, aside from "Mermail Abysstrite", in your Graveyard; Special Summon that target.

Gaios's precious wife. They even have inverse stats of each other. What we have here is a Shift on legs and a Mermail Monster Reborn on destruction, all while hiding behind a whopping 2800 DEF. You can bring this fine lady out by overylaying 3 Lv3 monsters on the field (made easier with Abyssdine), OR you can use our pal Bahamut Shark to bring her out with no Materials. A non-proper XYZ summon means she can't be revived by other means and no materials means she can't use her Shift effect, but with either method she can still SS a Mermail once she pops, and she's still a 2800 wall. She might as well be Bahamut's wife.
Run 1.




Now it's time to talk about Mermail Spells and Traps.



Abyss-sphere

Continuous Trap
Special Summon 1 "Mermail" monster from your Deck. The effects of the Special Summoned monster are negated. While this card is on the field, you cannot activate Spell Cards. When this card leaves the field, destroy that monster. Destroy this card during your opponent's next End Phase after activation.

A staple in the deck. Apropos to its artwork, this card was made for Abysslinde. A nightmare for your opponent, it brings out the Mermails you need FAST. Mess with your opponent at the end of their Main Phase 2 by summoning Linde to bring out Abysspike/Abyssturge to Pop+(Search/Recycle) and start your turn at an advantage. Summon a Mermonster for practically free and bring pressure to your opponent. Quickly bring out a Mermail to match a Level on your field for a quick XYZ play. Be wary of your inability to play Spells once its out. It laughs at the face of MST (but a post-activation chained MST laughs back at it) and is the #1 card you will be searching with Megalo.
Run 3.



Abyss-squall

Normal Trap
Target 3 "Mermail" monsters in your Graveyard; Special Summon those targets in face-up Defense Position, but their effects on the field are negated, cannot declare an attack, and are destroyed during the End Phase.

The "Atlantean Roar" for Mermails. A nice trap made searchable by Megalo, it triggers Linde during the End Phase and sets up your XYZ plays magnificently. Bring out any 2 matching levels and you have an instant XYZ. If anything, it sets up a whole wall of defenses in case you need it. You don't want it too early though.
Run 0-1.



Abyss-scale of the Kraken

Equip Spell
Equip only to a "Mermail" monster. It gains 400 ATK. When a monster your opponent controls activates an Effect Monster's effect: Negate that effect, then send this card to the Graveyard.

The first of three Abyss-scale cards in our disposal. Makes our normally weak Mermails into little beaters that can get over Rai-Oh and other commonly summoned level 4’s while negating their effects. The problem is that it suffers Doomcaliber Knight syndrome, removing itself from the field as soon as something your opponent controls on the field activates its effect. It's searchable for Megalo for some quick 2800 double-attacking action. If you get Abyssgaios out, though, it becomes useless.
Run 0.



Abyss-scale of the Cetus

Equip Spell
Equip only to a "Mermail" monster. It gains 800 ATK. When a Trap effect that was activated on your opponent's side of the field resolves: negate that effect, then send this card to the Graveyard.

Our second Abyss-scale, this time dealing with Traps. Also, gives twice as much power as Kraken. This card has a perk, as it can even negate Counter Traps as they resolve. That means this can stop a Solemn Warning and you'll be safe. It also has to stop the first trap because its mandatory. The problem is that most of the Traps we'd want to stop can be activated before Cetus can even be played, or are chainable to anything and can force it to disappear.
Run 0-1.



Abyss-scale of the Mizuchi

Equip Spell
Equip only to a "Mermail" monster. It gains 800 ATK. When a Spell effect that was activated on your opponent's side of the field resolves: negate that effect, then send this card to the Graveyard.

Just like Cetus, except with Spells. This one is actually useful though, since it can hit your opponent's staple spells, and more effectively than Cetus with traps because of chaining and responses and whatnot. While your opponent has control of which Spell they lose, even losing one Spell is extremely detrimental.
Run 0-1.



Abyss-strom

Normal Trap
Send 1 face-up "Umi" you control to the Graveyard; send all Spell/Trap Cards on the field to the Graveyard.

Clearly this was meant to be used with Lemuria. Too bad we don't use that.
Run 0.



Abyss-scorn

Normal Trap
Target 1 "Mermail" monster you control; that target gains 1000 ATK until the End Phaes. When this Set card is sent to the Graveyard: Send 1 monster your opponent controls to the Graveyard.

This is a very interesting card, as it's one of a few "trap traps" that punishes the opponent for going too heavy on the Heavy. If you get to use it, you can completely turn a battle around in an Honest-esque play (1000 makes a big difference when your Abysspike is about to be run over by Stardust Dragon). If they hit it while it's face-down, they lose a monster (and since the card is sent, Stardust or Zenmaines can't save it). Plus it's searchable by Megalo. Lost most of its perks when Heavy Storm got banned, but blind MSTs still happen (although your opponent is bad if they do that against Mermail).
Run 0-2.




If Mermails are the cannons, then Atlanteans are the ammunition. While the two can exist separately, they work best when in tandum with each other.



Atlantean Heavy Infantry

Level 2 / Sea-Serpent / Water
0 / 1600
While this card is face-up on the field, once per turn during your Main Phase, you can Normal Summon 1 Level 4 or lower Sea Serpent-Type monster in addition to your Normal Summon or Set. (You can only gain this effect once per turn.) When this card is sent to the Graveyard to activate a WATER monster's effect: Target 1 face-up card your opponent controls; destroy that target.

One of our main combo enablers, Heavy Infantry allows for surprise End Phase pops with the Linde+Sphere combo. He can be brought out by Diva, recycled with Sturge and Salvage, and is searchable with Dragoons. Dumping him with Megalo also provides instant destruction, as well as a multitude of other WATER monsters with discarding costs. Allows access to Rank 2's and Level 4 synchros with Diva. His extra Normal Summon allows easier Level 7 and 9 Synchro plays (namely Gungnir). When combined with Megalo, he can force things like Stardust and Bujingi Turtle to miss timing, since his effect is mandatory and must always come on the Chain Link before Megalo's optional effect.
Run 3.



Atlantean Marksman

Level 3 / Sea-Serpent / Water
1400 / 0
When this card inflicts Battle Damage to your opponent: You can Special Summon from your Deck 1 Level 4 or lower Sea Serpent-Type "Atlantean" monster, except "Atlantean Marksman". When this card is sent to the Graveyard to activate a WATER monster's effect: Target 1 Set card your opponent controls; destroy that target.

Another tool for our arsenal, Marksman can be discarded to pop set cards (not limited to back or front row). When using the Linde/Sphere combo on the opponent's Main Phase 2 after they set a trap, he can kill the trap before the opponent has the chance to use it. While his first effect is great, it's his second effect that shines with our monsters, quickly tacking on extra damage by summoning a Dragoons (though this power play was nerfed by Dragoons's Limiting). He can be searched out by both Pike and Dragoons and can also be recycled by Sturge and Salvage. Overlaying him and another Level 3 (such as Linde, Dine, or another Marksman) into Leviathan Dragon provides a 2500 beater that kills a backrow when he gains his muscle. The loss of 2 Dragoons and the fact that most of today's popular Traps are chainable has caused him to lose a lot of his power, though.
Run 2.



Atlantean Dragoons

Level 4 / Sea-Serpent / Water
1800 / 0
Level 3 or lower Sea Serpent-Type monsters you control can attack your opponent directly. When this card is sent to the Graveyard to activate a WATER monster's effect: Add to your hand 1 Sea Serpent-Type monster from your Deck, except "Atlantean Dragoons".

This card is insane. Instead of destroying opponents' cards, he offers consistency in adding whatever Sea Serpent you desire from the deck to the hand. Pike+Dragoons can mean adding double Marksman or a Heavy Infantry+Marksman to your hand, or a Megalo to dump that Marksman, or Moulinglacia. Having him on the field should be a rare occurrence, usually brought out by Marksman's effect and only happening when you're going for a WATER Rank 4 or for the Megalo Diva OTK. If he is on the field, you'll want to overlay him into Bahamut Shark, who will fetch Abysstrite, giving you a future Graveyard summon while searching for a Sea-Serpent.
Run 1. He's Limited, sadly.




We have a lot of non-specific WATER monsters at our disposal, most of whom will be a great boon to us.



Deep Sea Diva

Level 2 / Sea-Serpent / Water / Tuner
200 / 400
When this card is Normal Summoned, you can Special Summon 1 Level 3 or lower Sea Serpent-Type monster from your Deck.

The Tour Guide of Sea Serpents gives the deck flexibility in terms of Synchros and Rank 2 monsters. Tons of OTK potential alongside Megalo. One copy of her can fetch Marksman to fetch Dragoons for tons of damage. Coupled with Salvage, she makes for ways to quickly add Atlanteans to hand after she has made use of them. Searchable with Dragoons, recyclable with Sturge and Salvage.
Run 0-1. She too has been Limited.



Genex Undine

Level 3 / Aqua / Water
1200 / 600
When this card is Normal Summoned, you can send 1 WATER monster from your Deck to your Graveyard to add 1 "Genex Controller" from your Deck to your hand.

Another unique engine that both Mermails and Atlanteans can use. Undine is notable for activating Atlanteans straight from the deck, netting you advantage from a simple Normal summon while adding a Controller to your hand. He's searchable with Pike and recyclable with both Sturge and Salvage. Using Veiler or Fiendish Chain on him is futile as it is a cost to send the Water monster. But running him comes with the added curse of HAVING to run Genex Controller who, on its own, can clog your hand and give you dead draws, though he gives you more Rank 3 and Synchro options (especially when comboed with Dracossack or Aqua Spirit). Allure of Darkness is another way to use Controller.
Run 0-3 Undines. If you run 1 Undine, run 1 Controller. If you run 2-3 Undines, run 2 Controllers (3 is always too much).



Tidal, Dragon Ruler of Waterfalls

Level 7 / Dragon-type / WATER
2600 / 2000
If this card is in your hand or Graveyard: You can banish a total of 2 WATER and/or Dragon-Type monsters from your hand and/or Graveyard, except this card; Special Summon this card. During your opponent's End Phase, if this card was Special Summoned: Return it to the hand. You can discard this card and 1 WATER monster to the Graveyard; send 1 monster from your Deck to the Graveyard. If this card is banished: You can add 1 WATER Dragon-Type monster from your Deck to your hand. You can only use 1 "Tidal, Dragon Ruler of Waterfalls" effect per turn, and only once that turn.

This card is another game changer for our deck. Easy presence at the cost of banishing your monsters, a constant Lv7 is appreciated for those strong Rank7 plays. If he's in the Graveyard you are automatically at the advantage in a topdeck war. His 'Foolish Burial' effect activates Atlanteans (it's a cost) and Gunde too; discard Tidal+Gunde, dump Leed/Megalo, Gunde SS your Lv7 Mermail. This is also a good way to get Fishborg Archer into the Graveyard. You can't dump AND SS Tidal in the same turn since only one of his effects is allowed per turn.
Run 3. We also used to run 1-2 Stream, but he got banned, so...



Abyss Soldier

Level 4 / Aqua / Water
1800 / 1300
Once per turn, by discarding 1 WATER monster to the Graveyard, Return 1 card on the field to its owner's hand.

What is considered to be the original Abyss monster, this guy allows for easy outs to Synchros and Xyzs. Meshes well with your Atlanteans and your Gundes, can also Return a Sphere to the hand to Special summon another Mermail via Linde. He is a little slow though. Maybe a Side Deck out to Ophion?
Run 0-1.



Abyss Warrior

Level 4 / Aqua / Water
1800 / 1300
Once per turn: You can discard 1 WATER monster to the Graveyard to target 1 monster in either Graveyard; Return it to either the top or bottom of the Deck.

Abyss Soldier’s comrade, they almost share the same effects, though Soldier returns a card in the graveyard to either the bottom or top of the deck. This can interrupt your opponent’s graveyard set-up or allow you to topdeck whichever monster you want next turn, while at the same time activating your monsters' effects. Overall, that's not too impressive though.
Run 0.



Snowman Eater

Level 3 / Water / Aqua
0 ATK / 1900 DEF
When this card is flipped face-up: Target 1 face-up monster on the field; destroy that target.

Famous card for trumping Laggias and Thunder Kings with ease. It is a searchable wall (via Pike) that can destroy a monster while being reusable with Sturge and Salvage. Also notable for playing mindgames on your opponent with its pal, Linde.
Run 0-2 in the Side Deck.



Aqua Spirit

Level 4 / Aqua / Water
1600 / 1200
This card cannot be Normal Summoned or Set. This card can only be Special Summoned by removing 1 WATER monster in your Graveyard from play. During each of your opponent's Standby Phases, you can change the battle position of 1 of your opponent's face-up Monster Cards. Once changed, the monster must remain in this position for the rest of the turn.

A solid card to make Rank 4 plays easier. Abyss Dweller and Bahamut Shark are both great in certain matchups, and she makes them easier. Combined with Archer of Controller, she also makes Level 7 Synchros easier. Banishing Tidal for her summon will place another Tidal in your hand. Her effect has some benefits to it as well.
Run 0-3.



Fishborg Archer

Level 3 / Fish / Water / Tuner
300 / 300
If this card is in your Graveyard and you control no monsters during either of your Main Phases: You can discard 1 WATER monster; Special Summon this card from your Graveyard, but destroy all monsters you control at the beginning of this turn's Battle Phase, except for WATER monsters. You can only use the effect of "Fishborg Archer" once per turn.

This guy is a great card to have in a topdecking situation. He can make any Gunde or Atlantean you draw live. He's also great for Synchro Summons, or Rank 3 Summons. Searchable by Pike, recyclable by Sturge and Salvage.
Run 0-1.



Moulinglacia the Elemental Lord

Level 8 / Sea-Serpent / Water
2800 / 2200
Cannot be Normal Summoned or Set. Must be Special Summoned (from your hand) by having exactly 5 WATER monsters in your Graveyard, and cannot be Special Summoned by other ways. When this card is Special Summoned: Discard 2 random cards from your opponent's hand. This effect of "Moulinglacia the Elemental Lord" can only be activated once per turn. If this card leaves the field, skip the Battle Phase of your next turn.

The lord of all that is frozen himself, this card is what many people consider to be a Delinquent Duo on a 2800 body. Sound scary? It gets even more menacing considering Dragoons can bring him to your hand as soon as the first turn. Having 5 monsters in the graveyard is an easy feat for us with all the dumping and graveyard control we have at our disposal. He's generally better suited for Genex builds, in which he is very easily searched.
Run 0-1.



Dewloren, Tiger King of the Ice Barrier

Level 6 / Beast / Water
2000 / 1400
1 Tuner + 1 or more non-Tuner WATER monsters
Once per turn, you can Return any number of face-up cards you control to the owner's hand. For each card returned to the owner's hand by this effect, this card gains 500 ATK until the End Phase.

His effect might not seem to be much at first glance, but looks can be deceiving. His ATK boost is just a minor benefit of his real effect: bouncing your cards. Bunch of shenanigans with returning Atlanteans to the hand for Ammo use, and returning Sphere for an easy re-set and easy 500 ATK boost. He doesn't trigger any cards by himself, but it is a useful Level 6 among whatever else is out there.
Run 0-1. He's Limited, but using more than 1 would be silly.



Gungnir, Dragon of the Ice Barrier

Level 7 / Dragon / Water
2500 / 1700
1 Tuner + 1 or more non-Tuner WATER monsters
Once per turn: You can discard up to 2 cards to the Graveyard to target the same number of cards your opponent controls; destroy them.

If Dewloren is about control, then Gungnir is all about destruction, as should be obvious from his effect. But thanks to our Atlantean friends, discarding 2 can translate to destroying 4, or making some searches. He's also handy with Gunde and Hilde, since he triggers both of their effects as well.
Run 0-1.



Number 11: Big Eye

Rank 7 / Spellcaster / Dark
2600 / 2000
2 Level 7 monsters
Once per turn: You can detach 1 Xyz Material from this card to target 1 monster your opponent controls; take control of that target. This card cannot attack the turn you activate this effect.

Abyssgaios isn’t our only Rank 7 option. This monster right here has the ability to drastically alter the game in your favor. A permanent Change of Heart on a 2600 body is nothing to scoff at, allowing you to steal an opponent’s boss monster gives you a variety of options. From ending the game with a stolen BLS, or using the monster to Xyz or synchro this monster proves itself to be a staple in our deck.
Run 1-2.



Mecha Phantom Beast Dracossack

Rank 7 / Machine / Wind
2600 / 2200
2 Level 7 monsters
Once per turn: You can detach 1 Xyz Material from this card; Special Summon 2 "Mecha Phantom Beast Tokens" (Machine-Type/WIND/Level 3/ATK 0/DEF 0). While you control a Token, this card cannot be destroyed by battle or card effects. Once per turn: You can Tribute 1 "Mecha Phantom Beast" monster, then target 1 card on the field; destroy that target. This card cannot attack during the turn you activate this effect.

Another strong Rank 7 monster. If you've been paying the slightest bit of attention at all to the guide, you don't need to be told how easy it is to make this guy. He provides his own defense and pops troublesome cards for you. Also facilitates Synchro Summons with the Tokens.
Run 1-2.



Bahamut Shark

Rank 4 / Sea-Serpent / Water
2800 / 2100
2 Level 4 WATER monsters
Once per turn: You can detach 1 Xyz Material from this card: Special Summon 1 Rank 3 or lower WATER Xyz Monster from your Extra Deck. This card cannot attack the turn you used this effect.

A Gem-Knight Pearl with an effect. Neat. Great beater for the deck if you need it. The pool of monsters this guy can bring out is a bit underwhelming, but luckily our very own Trite makes up for it. They're like brother and sister, really. Using Atlantean Dragoons as material, this is a 2600 beater that gets a search every time you use its effect, which is to summon a 2800 wall that gets you a free Graveyard summon on death. The extra neato part about this guy is that rulings allows us to bring out a monster even after he has attacked, so make that your go-to Bahamut play.
Run 1.



Abyss Dweller

Rank 4 / Sea Serpent / Water
1700 / 1400
2 Level 4 monsters
While this card has an Xyz Material attached that was originally WATER, all WATER monsters you control gain 500 ATK. Once per turn, during either player's turn: You can detach 1 Xyz Material from this card; any card effects that activate in your opponent's Graveyard cannot be activated this turn.

The blanket buff is helpful to our monsters, and like all WATER Xyz monsters, using his effect with an Atlantean as a Material will trigger its effect. His effect is also helpful for tackling effects that activate in the Graveyard, specifically Dark Worlds and the mirror match.
Run 1-2.



Snowdust Giant

Rank 4 / Beast-Warrior / Water
2200 / 800
2 Level 4 WATER monsters
Once per turn: You can detach 1 Xyz Material from this card; reveal any number of WATER monsters in your hand, then distribute that amount of Ice Counters among face-up monsters on the field. All non-WATER monsters on the field lose 200 ATK for each Ice Counter on the field.

This guys a neat way to weaken opposing monsters. compared to Bahamut and Dweller though, he's pretty underwhelming.
Run 0-1.



Number 17: Leviathan Dragon

Rank 3 / Sea-Serpent / Water
2000 / 0
2 Level 3 monsters
Once per turn: You can detach 1 Xyz Material from this card; this card gains 500 ATK. If this card has no Xyz Material, it cannot attack your opponent directly.

He's a pretty standard Rank 3 in any Deck, but he also serves as a Bahamut Shark target here. We don't make Rank 3's often though, and under Bahamut he wouldn't be able to attack directly. Up to you to use him.
Run 0-1.



Armor Kappa

Rank 2 / Psychic / Water
400 / 1000
2 Level 2 monsters
Once per turn: You can detach 1 Xyz Material from this card; this card gains 1000 ATK or DEF. During the Battle Step, when a monster you control battles: You can discard 1 card; this turn, you take no Battle Damage and monsters you control cannot be destroyed by battle. You can only use this effect of "Armor Kappa" once per Duel.

Obviously tailor made for us. Fantastic with Diva to instantly make him. He sets off any Infantry attached to him. While he isn't infinitely superior to Gantetsu or Phoenix, he does have his uses. And if you're worried about his 1400 ATK should you decide to buff him offensively, his second effect will keep him alive for a turn so you can buff him again. Depends entirely on your Atlantean load, though he works with Gunde as well. Sadly, he's an OCG-exclusive. For now, at least.
Run 0-1 if you live in OCG land. The hit on Diva admittedly hurt his usefulness.


Other Extra Deck cards you can run at your own discretion:


Mist Wurm
Crimson Blader
Scrap Dragon
Stardust Dragon
Black Rose Dragon
Ally of Justice Catastor
Armades, Keeper of Boundaries
Armory Arm

Gaia Dragon, the Thunder Charger
Number 74: Master of Blades
Daigusto Emeral
Diamond Dire Wolf
Gagaga Cowboy
Lavalval Chain
Maestroke the Symphony Djinn
Number 39: Utopia
Mechquipped Angineer
Number 50: Blackship of Corn
Number 30: Acid Golem of Destruction
Temtempo the Percussion Djinn
Wind-Up Zenmaines
Gachi Gachi Gantetsu
Daigusto Phoenix




We also have plenty of WATER Spells and Traps to choose from, many of them released in Abyss Rising alongside our Mermails.



Salvage

Normal Spell
Select 2 WATER monsters with 1500 or less ATK in your Graveyard, and add them to your hand.

Not only does this let us recycle the three maidens, it also lets us get back the Atlanteans (except for Dragoons). Seeing how the deck revolves on a lot of hand dumping, this helps us out a ton. HOWEVER. It is pretty bad in the early game, and while it's great in the lategame, by that point you'll be discarding WATERs a lot less. The presence of Tidal and the Limiting of Deep Sea Diva also drops its usefulness. Salvage is a flawed card, but some people still swear by it. It's not a bad choice, exactly, just preference.
Run 0-2.



Lemuria, the Forgotten City

Field Spell
This card's name is treated as "Umi". All WATER monsters gain 200 ATK and DEF. Once per turn, during your Main Phase: While this card is face-up on the field, you can increase the Level of each WATER monster you control by the number of WATER monsters you control, until the End Phase.

Another Umi clone, this time made for Xyz monsters. This card grants you access to a wider variety of Extra Deck monsters; for example, if you’re running Diva, you can easily bring out a Rank 4 monster or a level 8 Synchro after summoning Heavy Infantry. This should only be used in a dedicated build, which isn't very common. This city really is forgotten.
Run 0.



Bubble Bringer
Continuous Trap

Level 4 or higher monsters cannot attack a player directly. During your turn: You can send this face-up card to the Graveyard to target 2 Level 3 or lower WATER Monsters with the same name in your Graveyard; Special Summon them, but their effects are negated.

A Gravity Bind that only works for direct attacks, which lets us bring back 2 of any of our Level 3 or lower WATERs (and we have a lot). The only ones we'd want to bring back are Linde and Marksman, and honestly we usually don't need to.

Run 0.