You can also untap it with Tidewater Minion (or the like) to tap 2 creature during a single combat. With a single Ice Floe you can trap a couple of creatures... In this, Ice Floe can be better than Maze of Ith

5/5, sometimes it can be so annoying, but perfect for a control strategy, against an aggro. We need some more weapons to fight aggro/midrange!

Edit:
@leomistico - Incorrect. You cannot use Ice Floe to tap a creature. You use Ice Floe to prevent a creature that attacks you from untapping. If you use Tidewater Minion to untap your Ice Floe, then the creature you had trapped will be released and will untap during it's owners next untap phase. Also, Ice Floe does not stop the attack. When your opponent attacks you, you use Ice Floe to prevent his creature from untapping, but that attacking creature still attacks. You still need to block it or take the damage from it.

@Khardiss: you didn't understand a couple of things. Let's read th... (see all)