Kathux, The Blightspine Dragon

Flying, Trample
Infect (This creature deals damage to creatures
in the form of -1/-1 counters and to players in
the form of poison counters.)
Whenever Kathux attacks, if you control six or
less dragon cards, Karthux, gets +2/+0, and gains
"whenever Kathux deals combat damage to a
player, if that player has five or more poison
counter's, you lose the game."