https://fategrandorder.fandom.com/wiki/Phantasmal_Princess

Phantasmal PrincessFate/Grand Order Wiki

So Black Grail with a lower Attack cap (2000 rather than 2400), without the 500 HP per turn demerit, but only for a single class. I suppose if you use servants like Summer Musashi, Vlad III or the upcoming Summer Ibuki, it isn't bad, but you probably won't bother with it if you need to finish it in gen pool.