Fortune Thief

As long as this little Rogue stays on the battlefield, you cannot lose to damage. Combat, burn to the face, a Fireball for fifty: all of it stops short and parks your life total at exactly 1. The replacement effect is continuous and indifferent to source or size, so the only paths around it are non-damage (poison, mill, decking, life loss that is not damage) or removing the 0/1 itself. That last clause is where the body becomes the liability: a 0/1 deals no combat damage and applies no pressure, and it dies to a single point of incidental damage or any spot removal, at which point the safety net evaporates the instant before the next hit lands. The morph cost is the real trick. Hidden under a 2/2 shell, the card refuses to advertise whether you are holding a vanilla blocker or a hard floor under your life total, and because combat damage no longer uses the stack, you flip it during the declare-blockers step (before damage) to set the cap on the swing already aimed at your head. That converts brittle blocking math into a bluff: the attacker has to guess whether your unknown morph is the card that breaks their lethal calculation. It sits in the conceptual neighborhood of effects that prevent the last point of damage rather than gaining life back, except this one scales to any number. A standing "not while I am here," paid for entirely by how easy it is to knock the guarantee off the table.