| Card Name: | Poseidra, the Atlantean Dragon | |
| Rarity: | Ultra Rare | |
| Type Line: | Monster | |
| Type Line: | Sea Serpent | |
| Type Line: | Effect | |
| Attribute Symbol: | WATER | |
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.