Tilonalli's Skinshifter

Once the ability of Tilonalli’s Skinshifter resolves, its new characteristics don’t change if the characteristics of the copied creature change or if the copied creature leaves the battlefield.

If an effect from a resolving spell or ability, such as that of Rallying Roar, begins to apply to Tilonalli’s Skinshifter before it becomes a copy of another creature, that effect will continue to apply.

Because attackers have already been declared, any abilities Tilonalli’s Skinshifter copies that trigger when it or other creatures attack won’t trigger.

Notably, Tilonalli’s Skinshifter won’t copy effects that make a noncreature permanent become a creature. If this causes Tilonalli’s Skinshifter to stop being a creature, it’s removed from combat.

Tilonalli’s Skinshifter copies the printed values of the target creature, plus any copy effects that have been applied to it. It won’t copy counters on that creature or effects that have changed its power, toughness, types, color, or so on.

If Tilonalli’s Skinshifter copies a creature that’s copying something else, it will become whatever the target is copying.