Krystal vs King RedEye
Here's another video by BvqR zxi5. In these two cutscenes, Krystal faces the giant Tyrannosaurus Rex-like boss, King RedEye. She looks pretty silly in some of this one, because her Staff isn't there and her eye animations don't match up to Fox's. That's just a side-effect of this method of switching Fox to Krystal. Pretty epic, regardless!