What comes to mind when you think of competitive WATER-Attributed archetypes in Yu-Gi-Oh? Crystron has to be one of the most modern examples, given its recent legacy support. Rikka counts, but it's usually mixed with other Plant stuff. Gishkis and especially Nekroz have had their time in the limelight. Decks like Marincess and Ice Barriers might have been rogue options. Frogs for sure have to be near the top of the list of competitive WATER archetypes in Yu-Gi-Oh, with a rich history in this game. With that said, arguably the most well-known WATER archetypes to competitive players have to be the Atlantean and the Mermail archetypes. These archetypes, while technically separate until 2024/2025 support, have been tied to the hip ever since both released to the game towards the tail end of 2012 and have always made a splash together ever since. The synergy between both archetypes has been by design since release, and the room for generic WATER support has always existed for the Deck. When many players think about WATER as an Attribute, the Atlantean Mermail Deck is usually quick to come to mind. The Deck has been able to top on and off for well over a decade now, and today I want to go through the history of Atlantean Mermails together to see how they made a splash on the competitive seen.
Diving In
We begin in October 2012 with the release of the Realm of the Sea Emperor Structure Deck, and while the Structure Deck would give us 5 new cards, only 3 would be relevant for the remainder of the history when it comes to Atlanteans and Mermails. The first is Atlantean Dragoons, a Level 4 who if sent to the graveyard to activate a WATER monster's effect, lets you add any Sea Serpent monster from your Deck to your hand. The amount of good Sea Serpent targets to search off this wasn't plentiful yet, with the best target without a doubt being Deep Sea Diva, but as the pool of Sea Serpents grew and the number of WATER monsters who sent cards as cost for their effects became more plentiful, it became commonplace for WATER strategies to use Dragoons as the cost to search any Sea Serpent in the game. Speaking of Deep Sea Diva, we also have two targets to summon off her in the form of Atlantean Marksman and Atlantean Heavy Infantry. Both these monsters also trigger effects if sent by the cost of a WATER monster's effect, with Marksman targeting and destroying a face-down card the opponent controls and Heavy Infantry doing the same for face-up cards. Marksman can also let you summon a Level 4 Atlantean Sea Serpent from your Deck if it deals battle damage, and Heavy Infantry also offers an additional Normal Summon of a Level 4 or lower Sea Serpent monster in addition to your Normal Summon or Set, giving the Deck a bit of swarming. Marksman could also combo off of Dragoons allowing your Level 3 or lower Sea Serpents to attack directly as well. These monsters had good effects when used as cost for WATER monster effects, and the on-field effects were decent themselves, but it would take the next release to make them relevant.
Fast forward a month to November 2012 and we would have the release of the Mermail archetype to give the Atlanteans a home to use their effects. The boss monster, Mermail Abyssmegalo could summon itself from the hand by sending 2 other WATER monsters from your hand to the graveyard, which would open up the room to trigger your Atlantean monster effects. On summon, you would then get to search for any Abyss- Spell/Trap directly from your Deck, and Abyssmegalo could tribute a WATER monster to attack twice in a single turn, giving you another way to trigger Atlantean effects while being able to get battle damage in. Abyssmegalo being a Sea Serpent also allows Atlantean Dragoons to search for him, which you could also trigger off of being discarded off Mermail Abysspike to search for any Level 3 WATER monster out of your Deck or Mermail Abyssturge to add a Level 3 or lower WATER monster from your graveyard to your hand. These could work with your Atlanteans, with Abysspike being able to grab Marksman, and Abyssturge recovering either Marksman or Heavy Infantry, but you also get Level 3 Mermail options with Mermail Abysslinde to summon any Mermail from the Deck if it is destroyed and sent to the graveyard, or Mermail Abyssgunde to revive a Mermail if she is discarded and sent to the graveyard, adding another effect to trigger off the Mermail discard effects alongside the Atlanteans.
The Abyss- Spell and Trap lineup was also pretty decent for the start. Abyss-scale of the Kraken is an Equip Spell that you can equip onto a Mermail for a 400 ATK boost, while also being able to negate the first monster effect the opponent would activate. Abyss-squall could summon 3 Mermail monsters with your graveyard, and even though their effects would be negated and they could not attack, you would get 3 bodies on the board to make Xyz plays at the time. The best search target early on, however, would be Abyss-sphere to summon a Mermail from your Deck with its effects negated, which would summon Abysslinde to hopefully be destroyed to summon a bigger Mermail out of your Deck, otherwise, Abyss-sphere would just destroy itself and your Abysslinde to achieve the same end goal.
Being an archetype from the Xyz-era, Mermail would get their own Rank 7 monster in the form of Mermail Abyssgaios, who requires 2 Level 7 WATER monsters to summon to keep him close to home, but he prevents Level 5 or higher monsters from attacking, and he has a Quick Effect to detach a material from himself to negate the effects of all face-up monsters the opponent controls with ATK less than his, which should cover a ton of ground with 2800 ATK. There were also generic WATER Xyzs released at the same time that Atlantean Mermails would run to this very day. Abyss Dweller is a generic Rank 4 who does turn off the opponent's graveyard effects, but he also boosts all WATER monsters by 500 ATK when he holds one as material, plus his detach effect can trigger Atlantean Dragoons. The same goes for Bahamut Shark, who does require WATER monsters to summon, but also can get you a free Rank 3 or lower WATER Xyz in return.
Outside all those cards, there was one more monster that, while would be generic WATER support, would almost always be associated with and run alongside the Atlantean Mermail Deck, and that is Moulinglacia the Elemental Lord. This behemoth requires exactly 5 WATER monsters to be in the graveyard to summon, which Atlantean Mermail can fulfill and not worry about not having this when the exact requirement is met because this is another Sea Serpent monster, allowing it to be a search target off of Atlantean Dragoons. Moulinglacia, on summon, would then discard 2 random cards from the opponent's hand, or their entire hand if they have 2 or fewer cards already. Atlantean Mermail always having access to this monster and having no issue with searching for it while meeting its requirements for summoning keeps the opponent on edge of most likely starting their first turn with 2 fewer cards than their opponent.
It's an overall good start for the Atlantean Mermail Deck and it would be enough to get the strategy able to top events out of the gate. They would not have all their tools yet, but a good game plan was there. They would use Genex Undine in the Deck to send your Atlanteans to be able to trigger their effects while searching for a Genex Controller, which alongside Deep Sea Diva was the only way this archetype was going to get to Synchro Summon considering they didn't have any Tuners of their own. While Brionac, Dragon of the Ice Barrier would be banned in the TCG in its pre-errata form before this strategy was released, they can still access Synchros not many other strategies could like Gungnir, Dragon of the Ice Barrier, who offered card destruction while being able to trigger your effects, and Dewloren, Tiger King of the Ice Barrier to put Atlanteans back in the hand for discard fodder. The only Rank 3 you would have at the time to trigger Atlantean Marksman would be Number 17: Leviathan Dragon, while a good generic Rank 2 WATER wouldn't exist for Heavy Infantry. Salvage is also a solid card in early builds to recover your Atlanteans and Mermails with 1500 ATK or less, giving more discard fodder for Abyssmegalo, Abyssturge, or Abysspike. It was a good foundation that would grow as more archetype support and generic WATER cards would be released.
The next bits of support would come in January 2013 with a few more cards that could be added to the Atlantean Mermail strategy. Mermail Abyssleed is a bigger version of Abyssmegalo who can also tribute monsters to rip cards from the opponent's hand, but it was mostly run as the biggest target for Abysslinde's destruction effect and was otherwise considered a brick due to needing 3 WATER monsters to discard to summon itself and only adds Abyss- Spells and Traps back from the rave to your hand in return. Mermail Abysstrite was the go-to target to summon off of Bahamut Shark for years since she was a Rank 3 WATER monster who summoned a Mermail back from the grave when she was destroyed and sent there herself. Abyss-scale of Cetus was similar to Kraken, but for Trap negation instead of monster effect negation. The support wave would have been considered pretty weak if we didn't get Mermail Abyssteus as a TCG exclusive.
Mermail Abyssteus is a Level 7 Aqua who summons himself from the hand by discarding any WATER monster, giving you a Level 7 body for a low cost while also triggering your effects of course. When summoned this way, Abyssteus would then search for any Level 4 or lower Mermail monster directly from your Deck, getting you to Normal Summons like Abysspike or Abyssturge if you want more ways to trigger your Atlantean effects, Abysslinde for a monster to set on the defensive, or Abyssgunde as discard fodder that would get you back a Mermail monster that could go with your Abyssteus to make a Rank 7 Xyz potentially. This is another case of the TCG giving an archetype that's currently being released powerful support that would have a surefire spot in the Deck, back when the TCG would do something like this of course.
May 2013 would come around and give Atlantean Mermail a little bit more direct support, which would be the last direct support they would see for nearly 3 years. Mermail Abyssocea could send a Mermail you control to the graveyard to summon Level 4 or lower Mermails from the Deck whose combined Levels equaled that of the sent monsters, which could set you up for certain Synchro or Xyz plays. You would also get Abyss-scale of the Mizuchi for your Spell negate to complete the trio of Equip Spells with negates. The best support for this archetype, however, would be indirect with the release of the Dragon Rulers and Atlantean Mermail being able to access Tidal, Dragon Ruler of Waterfalls and Stream, Dragon Ruler of Droplets.
Tidal was useful in the Deck for being able to summon itself by banishing 2 WATER monsters from your hand or graveyard, and being a Level 7 was more help for Atlantean Mermails to summon Rank 7s like Mermail Abyssgaios, Number 11: Big Eye, or the newly released Mecha Phantom Beast Dracossack. Tidal could also discard himself with any WATER monster to allow you to send any monster from your Deck to the graveyard, giving you a Foolish Burial while also being yet another way for you to trigger the effects of your Atlantean and some Mermail monsters. The same went for Stream, discarding himself and a WATER monster to summon a copy of Tidal directly from your Deck, getting you the big dragon without having to banish monsters as well as giving you the effect of one of your Atlantean monsters. The release of Dragon Rulers might have meant the format was going to be dominated by them and Spellbooks at that time, but Atlantean Mermail did get a chance to use the WATER Dragon Rulers to top the European WCQ in 2013.
The Deck's Been Hit!
September 2013 ended the dominance of Dragon Rulers and Spellbooks as all four Baby Dragon Rulers got banned alongside Spellbook of Judgment, but Konami still was going to hit the rest of what was likely going to be meta as the format became more diverse again. Of course, this leads to Atlantean Mermail being a prime target as it was one of the better Decks before the release of the Dragon Rulers and full-power Spellbooks. This was also where the TCG and the OCG went with different Forbidden & Limited Lists, so the Deck was handled differently depending on the region. The OCG put both Mermail Abyssteus and Abyss-sphere to 1, while the TCG opted for putting Atlantean Dragoons and Deep Sea Diva to 1, both of which would be hits the OCG would copy as they also reverse the choices they've made over time, but we'll follow the TCG version of the Deck from this point forward as differences don't become overly major in how the Deck plays.
As for how Mermail Atlantean performed, the Deck was still one of the top strategies of the format, even without Stream, Dragon Ruler of Droplets and both Atlantean Dragoons and Deep Sea Diva being on the list. Aqua Spirit would begin to see play around this time as a Level 4 that you can simply Special Summon by banishing a WATER from your graveyard, helping make a Rank 4 like Bahamut Shark while Dragoons remained limited. Tidal would also remain at 3 in Atlantean Mermail lists while it was allowed, as making Rank 7s was a strong part of the Atlantean Mermail strategy, plus Tidal still triggers Atlantean effects.
The turn of 2014 would lead to another hit relevant for the Atlantean Mermail strategy, as the four Dragon Rulers would go to 1, which included Tidal unfortunately for Atlantean Mermail, but it was still a top strategy as we didn't get many new archetypes that would force Atlantean Mermail out of the metagame, even if they could still compete. The last hit for the Deck comes in April 2014, as Mermail Abyssgunde goes to 1 to slow down your revival of monsters you can make Xyzs with, but once again Mermail Atlantean is a decent strategy, especially as the Deck reintroduces Genex Undine and Genex Controller back into the Deck. The end of Atlantean Mermail as a top-tier strategy would be the release of Duelist Alliance and how archetypes like Shaddoll, Burning Abyss, and Satellarknights power creep all the previous competitive archetypes and Decks out of the format, including Atlantean Mermail turning into a rogue strategy. It became salt in the wound then when Tidal also got banned in April 2015 due to Dragon Decks becoming too powerful with the release of Number 95: Galaxy-Eyes Dark Matter Dragon, so this Deck would return to the deep for well over a year as the new Decks would compete against each other.
The Prince of Atlantis Arrives
After a year and a half on the sidelines, Mermail Abyssgunde returning to 3 in January 2015, and Atlantean Dragoons returning to 2 in July 2015, the Deck got the revival it needed in January 2016 when the TCG imported Neptabyss, the Atlantean Prince. This little Level 1 monster is a searcher for any Atlantean monster at the cost of sending an Atlantean from the Deck to the graveyard, which simply meant you could send an Atlantean Dragoons from the Deck to the graveyard to search another copy of Atlantean Dragoons you could discard off a Mermail, which of course means Neptabyss triggers your Dragoons to get a search, making a Moulinglacia play much more consistent. Elder Entity Norden was also solid indirect support since he could revive Atlantean Dragoons after being summoned off Instant Fusion and make a Bahamut Shark to detach your Dragoons, or a generic WATER Xyz like Abyss Dweller and Number 101: Silent Honor ARK. The competition was tough with Decks like Performapal Pendulums, PK Fire, Monarchs, and Kozmo, but it was far from a bad strategy and could compete still from time to time. Neptabyss could also summon an Atlantean from the grave if sent to the grave to activate a WATER effect, letting you get Dragoons back for Rank 4 plays.
More indirect support would also come for Atlantean Mermail as the Deck gets a much better target to summon off of Bahamut Shark in the form of Toadally Awesome. This gives the Atlantean Mermail strategy access to an omni-negation that can also recover WATER monsters like Atlantean Dragoons. This would become the go-to target off of Bahamut Shark in the Deck as the rest of the targets would no longer see any play because Toadally Awesome was leagues better than what we previously had. You could also use a small Frog package of Swap Frog and Ronintoadin in the Deck since they are Level 2 Aquas that could generically make Toadally Awesome. Sure Swap Frog's Special Summon effect wouldn't trigger Atlanteans, but you could get the effects of Mermail Abyssgunde or even Mermail Abysshilde to get bodies on the field, or put Mermail Abyssmander in the grave to adjust the Level of a Mermail to make an Xyz Monster. It still had tough competition at this point with ABC, Metalfoes, Blue-Eyes, and Paleo Frogs being top strategies, but it again could still keep up with the power plays it has and made for a solid Deck for even a YCS.
Zoodiac would again knock Atlantean Mermail off the YCS level, which was already a weaker position than its prime due to the power level of the game increasing that even Neptabyss wasn't going to turn Atlantean Mermail into being Tier 1, but it would remain on a regional level, especially after the release of Link Monsters. For one, the Deck does have a new Synchro toy they could play with in the form of a post-errata Brionac, Dragon of the Ice Barrier to bounce cards and trigger Atlantean effects. Atlantean Dragoons would also be at 3 in May 2018, so the Deck had every powerful tool it could ask for besides Tidal and multiple copies of Deep Sea Diva, and Elder Entity Norden being banned due to its role in Zoodiac, meaning the best Instant Fusion target for the Deck became Rare Fish. Mermail Atlantean didn't need a lot of zones to do a Bahamut Shark and Toadally Awesome play, and it wasn't hard to put up a Mistar Boy for example to get the two zones needed at this time. The ability for Mermail Atlantean to make Rank 7s did mean you could use Number 42: Galaxy Tomahawk to make a mass amount of Link Monsters, setting up Firewall Dragon co-links with great ease.
Another indirect tool would also come for Atlantean Mermail in the form of Knightmare Mermaid due to it being a WATER Link-1 whose discard could trigger your Atlanteans while you could potentially get the opponent under a Knightmare Corruptor Iblee lock and Extra Link, along with adding additional hand rips on top of Moulinglacia the Elemental Lord as Galaxy Tomahawk allowing for so much Link shenanigans meant you could run Topologic Gumblar Dragon. Knightmare Mermaid also being a generic bridge into the Orcust engine meant Mermail Orcust was also an option, even if it wasn't the best version of Orcust at the time. It could also be a Sekka's Light Deck since Atlantean Mermail didn't need a lot of Spells & Traps. Nothing got Atlantean Mermail beyond the regional level, but it was at least still around.
A Legacy Resurfacing
And now we come to modern-day Atlantean Mermail. At this point, the Link restrictions were lifted off of Synchro and Xyz Monsters, Deep Sea Diva would finally be back at 3, and they had a new tool in the form of Deep Sea Minstrel to check for hand traps like Ash Blossom & Joyous Spring or Nibiru, the Primal Being that would slow your combos down while also being yet another way to trigger Atlanteans. Nothing there would get Atlantean Mermails to the next level again, but thankfully Rage of the Abyss gave us new Atlantean Mermail support towards the tail end of 2024, and it's great support on top of that while also officially tying Atlanteans and Mermails together as archetypes, even if this new support would finally start locking the Deck into only making WATER plays. Abyssrhine, the Atlantean Spirit is a new Level 3 who is always treated as a Mermail and could tribute itself from the hand alongside any Atlantean and Mermail in your hand or on your field to let you take any Level 7 Fish, Sea Serpent, or Aqua monster and either let you add it to your hand or Special Summon it. This gave you more ways to trigger Atlanteans while being able to search for Mermail Abyssteus, as Abyssmegalo is not enough for modern builds, or you can now access Superancient Deepsea King Coelacanth to summon a bunch of monsters from the Deck for Synchros and Xyzs, which includes Bahamut Shark into Toadally Awesome or LeVirtue Dragon to search for Virtue Stream. Abyss Dweller is also still legal and you can make Number 4: Stealth Kragen for removal and burn against the opponent. There are also solid WATER Synchros you could access like Trishula, Dragon of the Ice Barrier, Adamancipator Risen - Dragite, and Swordsoul Supreme Sovereign - Chengying by running solid WATER Tuners like Gluttonous Reptolphin Greethys. Speaking of Xyzs, however, we also have Mermail Shadow Squad, who is always treated as an Atlantean, and can let you discard a WATER monster to change the Levels of all WATER monsters you control to 7 for the turn to make Mermail Abyssgaios easier and potentially slap the new Poseidra Abyss, the Atlantean Dragon Lord on top and Link it away to get back 3 Level 3 WATER monsters, plus he can detach 2 materials from himself to return up to 3 cards the opponent controls to the hand. Shadow Squad also summons a Level 4 or lower Atlantean or Mermail from the Deck if sent to the grave to activate a WATER monster's effect, summoning Atlantean Dragoons or Mermail Abysspike, the latter of which can search Ghost Sister & Spooky Dogwood for time as well.
I should also mention the Deck previously got a Link-2 in 2019 in the form of Mermail Abyssalacia, which wasn't too relevant to Atlantean Mermail until the modern builds since it can trigger Atlanteans on the opponent's turn and search for your Mermails, and it can also climb you into the Link-3 Mermail King - Neptabyss, who gives your WATER monsters it points to some targeting protection, and lets you take an Abyss- Equip Spell from your Deck or graveyard and either add it to your hand or equip it to this card each time a WATER monster is sent to the graveyard to activate a card or effect, working with the new Abyss-sting Triaina for an archetypal Premature Burial. There are also a bunch of other indirect tools Mermail Atlantean could play with like Marincess Coral Anemone for revival, or Abyss Keeper to summon your Coelacanth you might hard draw. It's also one of few Decks that can run Dominus Impulse since using it from the hand doesn't lock you from your WATER monster effects.
The support doesn't end there, as a second wave of Atlantean Mermails would come in Supreme Darkness in January 2025. The main support piece would be Poseidra, the Storming Atlantean, who can simply be summoned from the hand by sending a WATER monster from your hand or face-up field to the graveyard, and on summon you can send an Atlantean or Mermail from your Deck to the graveyard to return a card the opponent controls to the hand, giving you two ways on this card to trigger Atlantean effects. They also got a new Rank 7 in the form of Abysstrite, the Atlantean Spirit, who on Xyz Summon can revive a Level 7 or lower Fish, Sea Serpent, or Aqua monster to extend your plays, plus it's an Xyz you can put Poseidra Abyss on top of without wasting your Mermail Abyssgaios. The Rank 7 Abysstrite could also detach a material from herself to set an Abyss- Trap from the Deck, which if you were to play a target, it'd likely be the new Abyss-steam for draw power. Abysstrite could also revive a Barrier Statue of the Torrent you send via your other Atlantean Mermail effects, putting a lock from Special Summons of monsters that aren't WATER monsters, which won't be relevant to Atlantean Mermail as they are exclusively WATER monsters for the most part. The second wave of Mermail Atlanteans was great for the Deck, just like the first, and helped the strategy reach Top 4 at a recent YCS in 2025 and even be 2/3rds of the winning team at at the 3v3 YCS in Las Vegas in March 2025.
Conclusion
It's always impressive when a Deck is competitive on release, takes a break, and can once again become competitively viable with even just a single card of legacy support, but it becomes even more impressive when that feat happens twice. Mermail Atlanteans were strong from late 2012 to mid-2014, getting another run in 2016 with Neptabyss and Toadally Awesome, and then becoming a good Regional Deck until it got even more legacy support in late 2024 and early 2025 and returning to the YCS level is great. It never really had a strong performance at the World Championship due to Dragon Rulers being dominant in 2013, the TCG and OCG hits combined being too much in 2014, and Blue-Eyes being the best Deck in 2016, but with nothing hit to Atlantean Mermail as of late March 2025, there might be a chance it can finally show up at the 2025 event against Blue-Eyes and Maliss to name some of the likely candidates as of this moment. It's unknown how long this run of relevance for Atlantean Mermail will go for the third time, or if the Deck will get hit in the TCG again due to it performing much better over here compared to the OCG, but we've had a good run with Atlantean Mermail and when it leaves the meta again as a top Deck, it'll be fun to see if a fourth wave of support in the distant future gives it another run at the top tables.
