Well, whatever the Tyrant was doing with his head, someone wasn't going to give him the chance to do anything else.

"Holy Arrow!" Angewomon shouted from the air as she flew over the battle, launching an arrow of light... and letting it explode in front of the giant monster. Sure, she and Hikari saw the post on the Omnicrom, but if this was really a mutated crew mate, then they couldn't kill him.

Or rather, she couldn't, because Hikari wouldn't let her.