Poseidra, the Ultimate Atlantean Dragonlord

 © 1996 Kazuki Takahashi 

**Effect:
1 WATER Synchro monster + 2 WATER monsters
When this card is Fusion Summoned; Destroy all monsters your opponent controls whose ATK is less than the number of Spell/Trap cards on the field x 500. Face-up Level 4 or lower WATER monsters you control gain 500 ATK and they cannot be destroyed by battle. Once per turn: If this card would be destroyed; Discard 1 card from your hand instead.