Phyrexian Crusader

First strike, protection from red and from white
Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

The List

Secret Lair Drop

Mirrodin Besieged

If Phyrexian Crusader blocks or is blocked by a creature without first strike or double strike, the damage dealt by Phyrexian Crusader results in -1/-1 counters that will affect how much damage the other creature assigns (if it’s still on the battlefield).

Poison Counter

(A player with ten or more poison counters loses the game.)