Ifrit HM needs to be reworked entirely. If you don't have a PLD to stun Eruption, you lose. If you don't have a BLM or SMN to Limit Break the Nails, you lose. It's just stupid, and honestly skill plays very little part in the whole run. All it is, is "Can you press this one button at the right time? Then you win." If they got rid of the required interrupt and instead added more of those Crimson Path dash attacks or something it would make for a far more interesting fight. Heaping all the responsibility on one/two players is poor design.