The Holy Grail still has it's uber-healing ability, but in a call back to the Kamoshida fight, we can send a party member to shut it down. Thereafter the fight's first phase is pretty straightforward.

The Holy Grail still has it's uber-healing ability, but in a call back to the Kamoshida fight, we can send a party member to shut it down. Thereafter the fight's first phase is pretty straightforward.
So, the Mementos palace is essentially two palaces with a giant cutscene in-between. The second half is a relatively small and linear affair where you fight SMT's version of the four Archangels (as the Big Bad considers himself a god.)