Permeating Mass

If Permeating Mass becomes a copy of another creature before its triggered ability resolves, the damaged creature will become a copy of that creature.

A creature dealt lethal damage during combat won’t survive long enough to become a copy of Permeating Mass. If Permeating Mass is dealt lethal damage during combat, the creature Permeating Mass dealt damage to still becomes a copy of it.

The damaged creature copies the printed values of Permeating Mass. It won’t copy counters on Permeating Mass or effects that have changed its power, toughness, types, color, or so on. Notably, this means that a creature that becomes a copy of Permeating Mass has the ability to permeate other creatures as well.