My issue with builds like this is Fafnir stopped losing HP a little over a minute into the 6+ minute combo, and this is all builds like this are good for in an actual fight. Sure, it looks cool, but the phase shift made this completely extra when it was actually doing no damage for the vast majority of the combo. I get that it is to see just how high you can get the burst, but it's not a very practical build IMO.