Whenever Derevi, Empyrial Tactician enters the battlefield or a creature you control deals combat damage to a player, you may tap or untap target permanent.
: Put Derevi onto the battlefield from the command zone.
10/17/2013 You can activate Derevi’s last ability only when it is in the command zone.
10/17/2013 When you activate Derevi’s last ability, you’re not casting Derevi as a spell. The ability can’t be countered by something that counters only spells. The ability isn’t subject to the additional cost of casting commanders from the command zone.