Kronu, Home Of The Broken

{t}: Add one {u}, {b}, or {g} to your mana pool.
Creatures get -1/-1 and cannot get power and toughness boosts.
(No creature can get +X/+X or +1/+1. +1/+1
counters don't give any bonus to the creature's power
and toughness.)
"This is our world!"
-Bek, Destroyer Of Cities