KMST 1.2.454 - Resistance Hyper Skills, November Update

It ignores Damage Reflect for the first 10% of Metamorphosis' duration. That's why it has a cooldown now, so you don't spam it every 20 seconds to be immune from Damage Reflect.

Oh that's dandy, is that what the little fluff ball with wings animation is, to let you know when your 20 seconds are up. That means soloing empress/PB, you can time when to cast meta to coincide with her reflection, but other than the soloing scenario, pretty impractical.