Realm of the Sea Emperor Structure Deck Single Cards

You can Tribute 3 Level 3 or lower WATER monsters; Special Summon this card from your hand or Graveyard. When you do: Return all Spell and Trap Cards on the field to the hand, and if you do, if 3 or more cards are returned to the hand by this effect, all monsters your opponent currently controls lose 300 ATK for each.

All face-up 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 1 Sea Serpent-Type monster from your Deck to your hand, except Atlantean Dragoons.

When this card inflicts Battle Damage to your opponent: You can Special Summon 1 Level 4 or lower Sea Serpent-Type Atlantean monster, except Atlantean Marksman, from your Deck. 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.

During your Main Phase, you can Normal Summon a Level 4 or lower Sea Serpent-Type monster in addition to your Normal Summon/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.

The Great Ocean Lord, who reigns over the depths, is served by these lancers. Deep-sea creatures exist in fear of facing the stream of attacks their lances are capable of.

This card gains 800 ATK while you control a face-up Fish, Sea Serpent, or Aqua-Type monster other than this card.

If there is another face-up Fish, Sea Serpent, or Aqua-Type monster on the field: You can Tribute this card to target 1 Spell/Trap Card on the field; destroy that target.

After damage calculation, if this card battles an Effect Monster: Negate the effects of that monster (including in the Graveyard). You must control another face-up WATER monster to activate and resolve this effect. If this card would be destroyed, you can destroy 1 face-up Level 3 or lower WATER monster you control instead.

All Fish-Type, Sea Serpent-Type, and Aqua-Type monsters you control gain 400 ATK.

When this card is Normal Summoned: You can Special Summon 1 Level 3 or lower Sea Serpent-Type monster from your Deck.

Once per turn: You can target 1 face-up Level 3 or lower monster you control; equip that target to this card. (You can only equip 1 monster at a time to this card with this effect.) While equipped to a monster by this effect, this card gains 800 ATK. If this card would be destroyed, you can destroy the monster equipped to it with this effect instead.

You can send 1 face-up Umi you control to the Graveyard to target up to 2 cards your opponent controls; send those targets to the Graveyard.