Infected Defector

A 4/3 for five mana is a body nobody builds around on its own merits, which is the tell that the real card is what happens after it dies. Incubate 3 converts a death into a delayed 3/3: an Incubator token that lands right away as a made-now artifact but stays a paperweight until you can spare the mana to transform it into a creature. That deferral is the entire mechanic. Incubate splits the reward across two moments, an artifact produced immediately and a body cashed later, so the Knight pays off best in decks that can spend it on their own terms (a sacrifice outlet, a chump into combat) and still net a threat. It reads like a two-for-one and plays like a patient trade, because the incubator contributes nothing to a defense until you have the mana to complete the transformation. The Phyrexian oil doubles as resilience: answer the front half and the controller simply hands themselves a fresh problem, one that has to be dealt with a second time and on a turn of their own choosing rather than yours. That timing wrinkle is what makes the death trigger genuinely annoying to play against; you can kill the creature, but you cannot decide when the follow-up arrives.