Slushy (Platinum Secret Rare) - Quarter Century Stampede

When this card is Normal Summoned: You can send 1 "Slushy" from your Deck to the GY. If you have 3 copies of "Slushy" total, either banished and/or in your GY (combined): You can banish this card from your GY, then target 1 Level 5 or higher Sea Serpent monster in your GY; Special Summon that target. You can only use this effect of "Slushy" once per turn.