Conan, Enraged Barbarian

Trample, haste (This creature can attack
and {t} as soon as it comes under your control.)
When Conan, Enraged Barbarian enters the
battlefield, each creature target opponent
controls gets -1/-1 until end of turn.
Put a +1/+1 counter on Conan, Enraged Barbarian for each creature that died this way.