Mutated Undead

Undying (When this creature dies, if it had no
+1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.)
As long as Mutated Undead has a +1/+1 counter on it, it has first strike and infect.
"It once looked like a human. Now it's something.. something more terrible."