Originally Posted by
Garrac
it's really hard to tell what the hell is Grail since the only author that gave her some atention, James Robinson, did a very poor job on deciding what to do with her and she ended up being just Darkseid's sidekick. Later Willow Wilson put her as a villain for her Themyscira arc, but you clearly could tell that she had intended another character for the role, since it feels kinda forced that half of the amazons would follow Grail.
So, to sum it up, we've had Grail in an arc where she was the sidekick for another villain, and in another arc where she's probably making it up for another character.
You could say she's Wonder Woman physical oponent rn, but what we've read is very inconsistent. grail is a blank paper on which anyone can write anything at this point, tbh.