If another card(s) you control leaves the field by an opponent's card effect, while this card is in your Monster Zone (except during the Damage Step): You can activate this effect
They mutate into the creature on top plus all abilities from under it.) Reach, trample Whenever this creature mutates, destroy target artifact or enchantment an opponent controls
After a while, it became a staple of the tournament scene because it allows control decks to reliably kill without playing any creatures at all, turning lots of their opponents' cards useless by denying them targets
High Tide is a one-mana blue instant that provides ramp for one turn, but depending on when you cast it, it can pay massive dividends
2006-09-25 Sudden Spoiling affects only permanents that are creatures on the battlefield under the targeted player's control at the time Sudden Spoiling resolves
You need to really know your deck, and your chances of drawing a particular card, to get the most out of it