Calamatus, The World Plague

Infect, Haste, Trample, Flying, Double Strike
When Calamitous, The World Plague
enters the battlefield Turn all Permanents your
opponents control into 0/3 defenders,
then put a -1/-1 counter on creatures
your opponents control, then put a
infect counter on all players.
When you deal infect damage to a player
deal that much damage to all other opponents
When you cast a spell Proliferate.