Tar Sleeper

When Tar Sleeper enters the battlefield, put a
bind counter on target creature (If a creature has
a bind counter on it, it can't attack or block.)
When Tar Sleeper deals damage to another
creature, if that creature died this turn, you may
have that creature's power and toughness
become Tar Sleeper's power and toughness until
Tar Sleeper is dealt damage.
"That's a pretty rock..."