Grotag Thrasher

Oracle Text

Whenever Grotag Thrasher attacks, target creature can't block this turn.

Card Rulings

3/1/2010 The targeted creature is prohibited from blocking any creature this turn, not just Grotag Thrasher.
3/1/2010 Grotag Thrasher’s ability can target any creature, not just one the defending player controls. For example, if you want that player’s creatures to be able to block this turn, you can target Grotag Thrasher with its own ability.