Cowards can't block Warriors.
: Target creature becomes a Coward until end of turn.
: Target creature becomes a Warrior until end of turn.
5/1/2007 Coward is a new creature type.
5/1/2007 Each of the activated abilities replaces all creature types the affected creature may have had.
4/1/2008 Note that the exact wording of this card has changed since it was printed in the _Future Sight_(TM) set, but its functionality is the same.