Rhino-Souled Rage Stoker

When Rhino-Souled Rage Stoker enters the
battlefield, you may discard two cards to put
an Umbra counter on him.
An Umbra counter is an attached enchantment.
While on is on him he gains +2/+2, and may
assign his combat damage as though it weren't
blocked.
Remove an Umbra counter from him; Destroy
target artifact or give him Indestructible until
the end of the turn.