You can target 1 face-up card your opponent controls; destroy 1 "Icejade" monster you control, and if you do, negate the targeted card's effects until the end of this turn (even if this card leaves the field).
If a face-up WATER monster(s) you control leaves the field by your opponent, except by being destroyed (except during the Damage Step): You can take 1 "Icejade" monster from your Deck, and either add it to your hand or Special Summon it.
You can only use each effect of "Icejade Erosion" once per turn.