I saw Remilia "almost lose" to Ninja Megazord earlier, probably the match you're talking about. He just hits really goddamn hard. He could have actually won it if he hadn't knocked Remilia out of her first card, thus refilling her health.
Random information follows: Immaterial and Missing Power Remilia and Patchouli both operate on that game's story mode system, as opposed to normal rounds. They're generally incredibly easy to beat for the first round and then become impossible for 90% of characters after that.
However, I've noticed that sometimes they seem to get hit so hard at the end of the first round that they lose multiple of their rounds and can bug out a bit at the start of round two and lose that as well.
Also, if someone
almost kills them but never makes the last hit, they can lose on time as they retain their health through rounds. However, this requires some significant dodging skills, because the other guy has to survive to the time out