Phyrexian Unlife
b4a1e16a-39f0-47ab-aba8-73e82ba9ab18
$2.12 CND
You don't lose the game for having 0 or less life.
As long as you have 0 or less life, all damage is dealt to you as though its source had infect. (Damage is dealt to you in the form of poison counters.)