Xedd Operative

Xedd Operative can't be blocked by creatures
with power 4 or greater.
Whenever another artifact enters the battlefield,
put a +1/+1 counter on Xedd Operative.
Modular 1 (This creature enters the battlefield with
a +1/+1 counter on it. When it dies, you may put its
+1/+1 counters on target artifact creature.)