Emrakul Brood (It that Rides as One) - Doesn't care about physical damage

As it drew near, her blade flashed out and cut two long gashes across what should have been the horse's neck. Brownish something dripped from the wounds—not blood; it writhed and squirmed like worms wriggling beneath an overturned rock. And the creature didn't seem to notice.

A hoof at the end of something that was not a leg lashed out at her. She batted it aside, cutting into the flesh just above the hoof, which this time brought a seepage of yellowish pus. But as she parried to one side, a tentacle—perhaps one of the rider's arms, before—slapped her from the other side. The side of her face stung...and then it didn't. Her skin went numb and cold where the fleshy mass had struck her.

She staggered backward two steps, shifting her sword to her other hand as the numbness spread down her neck to her shoulder. The thing followed her and reared up to strike her again, but then her gryff swooped down and drove its beak through the core of the creature's fleshy mass. A howling ululation rose from several mouths yawning open in its body.

She sank her blade deep into the thing—right above a foot still resting in a stirrup, she realized with a jolt of revulsion—and the volume of its cry increased. Several other cathars had come to her aid, and they swung heavier swords and axes until the horror lay twitching at their feet.

SAINT TRAFT AND THE FLIGHT OF NIGHTMARES