Water Deck A Water Deck is a deck type based around WATER Attribute monsters . While some choose to build their decks around certain cards ( i . e . A Legendary Ocean , Superancient Deepsea King Coelacanth , Sea Lancer ) , and others around certain archetype s ( i . e . Atlantean , Gishki , Mermail ) , most can benefit from usual WATER support cards , specially Salvage and Spiritual Water Art - Aoi . Water Decks have been hit several times by the Forbidden List , banning " Fishborg Blaster " , a powerful WATER Tuner , " Substitoad " , a key monster in the Frog Engine and Frog FTK , and two Synchro Monsters of the Ice Barrier archetype , " Brionac , Dragon of the Ice Barrier " and " Trishula , Dragon of the Ice Barrier " , though the latter has since been removed . Deck Types . A Legendary Ocean Deck . A Legendary Ocean decks rely on their Field Spell Card , " A Legendary Ocean " , hence the name . " A Legendary Ocean " decreases the Level of all WATER monster in both players ' hand and field by 1 . This allows summoning of powerful WATER monsters like " Giga Gagagigo " without any tributes , and decreasing the number of tributes needed for even stronger monsters , like " Levia - Dragon - Daedalus " . Having their Levels decreased , WATER monsters are also immune to cards like " Gravity Bind " , so it will only lock down their opponent , and also supported by " Hammer Shark " and " Hydro Pressure Cannon " . " A Legendary Ocean " is also treated as " Umi " , wich is required for the effects of many WATER monsters . Utilizing Beatdown Methods . Water monsters can also be played to destroy monsters , spells , and / or traps to perform multiple direct attacks . In this case , A Legendary Ocean does not serve as big of a role whereas cards like Umiiruka may help a little more since it adds more significant ATK strength . Frog Deck . Frog Decks are based around the Frog archetype . They consist of low - level Aqua - Type WATER monsters . Although weak on their own , they are mostly used for Tribute fodder and Xyz Summon s . The main monster , " Treeborn Frog " , is Special Summoned during each of your Standby Phase s as long as there are no Spell / Traps or other " Treeborn Frogs " on your side of the field . " Swap Frog " can Special Summon himself from your hand by discarding 1 WATER monster , and can return himself to the hand as well . When it ' s summoned , it can dump another Frog to the Graveyard , like " Treeborn Frog " or " Ronintoadin " . " Ronintoadin " can banish 1 Frog monster from your Graveyard to Special Summon himself from the Graveyard . He is mostly used for Rank 2 Xyz Summons , like " Gachi Gachi Gantetsu " and " " . Frog Monarchs / Frognarchs . Frognarch decks use the Frog Engine to Summon " Monarch s " , triggering their effects . The first step is to send " Treeborn Frog " to the Graveyard , usually with " Swap Frog " ' s effect . He is then used as Tribute in the following turns for the powerful Monarchs . " Caius the Shadow Monarch " banishes 1 monster on the field when he ' s Tribute Summoned , and " Mobius the Frost Monarch " can destroy up to 2 Spell / Traps on the field . Another ace monster , " Light and Darkness Dragon " can completely lock - down the game , negating any effect that activates , including " Treeborn Frog " . " Enemy Controller " , for being a Quick - Play Spell Card , can be used when " Treeborn Frog " is summoned , tributing him to take control of an enemy monster , and since it ' s still the Standby Phase , " Treeborn Frog " is Special Summoned again , thus giving you control of an enemy monster until the End Phase for no cost . Lancer Frogs . Lancer Frogs decks function like Frognarchs , however , they focus on their ace monster , " Sea Lancer " . " Sea Lancer " can equip any number of banished WATER monsters to himself , giving him a 1000 ATK boost , and negating its destruction by sending one of the equiped monsters instead . " Ronintoadin " is essential to this deck , as he is the one who banishes Frogs for " Sea Lancer " . Cards like " Aqua Jet " and " Horn of the Phantom Beast " are used to support " Sea Lancer " . Coelacanth / Fish Synchro Deck . Coelacanth Decks focus on Synchro Summon ing through the effect of their main monster , " Superancient Deepsea King Coelacanth " . " Coelacanth " can discard 1 card to Special Summon as many Level 4 or lower Fish - Type monsters from the deck as possible . The main monsters to be summoned are " Royal Swamp Eel " , for being a Level 4 Tuner and " Oyster Meister " , for Special Summoning a " Oyster Token " to be used for a future Synchro Summon . Usually 2 " Royal Swamp Eels " are summoned , then " Oyster Meister " and a Level 4 Fish monster . Then the player can go for Synchro Summons from Level 7 to Level 9 , wichever he finds best . Gishki Deck . Gishki Decks use the Ritual Summon based Gishki archetype to quickly summon powerful Ritual Monster s . Their main Spell Card , " Gishki Aquamirror " , can only Ritual Summon by tributing monsters with a level equal to the Ritual Monster , but it can recycle itself by shuffling itself to the Deck ( while it ' s in the Graveyard ) and adding a Ritual Monster from the Graveyard to the hand as well . The two main non - Ritual monsters of this archetype are " Gishki Vision " and " Gishki Shadow " , that can discard themselves to search a Gishki Ritual Monster or a Gishki Ritual Spell , respectively , can be used as the whole tribute for the Ritual Summon of a WATER monster , and can be recycled with " Salvage " . All of the Gishki monsters have even levels . Zeal Gigas / Gustav Max OTK . The Zeal Gigas / Gustav Max OTK uses the power of " Gishki Zielgigas " and " Superdreadnought Rail Cannon Gustav Max " to finish the opponent in one turn . First , to clear the field , one can use " Zeal Gigas ' " effect to shuffle a card in the Deck by paying 1000 Life Points and drawing a Gishki monster . " Zeal Gigas " can be Ritual Summoned many times by recycling it with " Gishki Aquamirror " and using the " Zeal Gigas " already on the field as the tribute . After the field is clear , and you have at least 2 " Zeal Gigas " on the field , attack directly , then Overlay for " Superdreadnought Rail Cannon Gustav Max " to finish the enemy with its effect . This deck is very versatile , and it works well even if you can ' t OTK the enemy . Atlantean Deck . Atlantean Decks focus on clearing the field using the effects of the Atlantean monsters , mainly " Atlantean Heavy Infantry " and " Atlantean Marksman " . Both have their effects activated when they are sent to the Graveyard to activate the effect of a WATER monster , wether they were in the hand , deck or detach ed . " Atlantean Heavy Infantry " destroys a face - up enemy card , and " Atlantean Marksman " destroys a face - down enemy card . Atlanteans can also swarm the field through " Deep Sea Diva " and " Atlantean Marksman " , setting up Synchro Summons , usually for " Ally of Justice Catastor " and " Gungnir , Dragon of the Ice Barrier " . To activate their effects , cards like " Abyss Soldier " , " Genex Undine " , " Mermail Abyssmegalo " and " " are used in the Deck .