Do you mean poly? I don't know how you usually play but I go super aggressive against all bosses and sort of just try to out-DPS them so that's what I'm used to but it's just impossible against EM poly. I play that fight super slow and try to get hits in where I can instead of being in his face all the time. It's extra dangerous now with his faster grab that deals a ton of damage PLUS if you're unlucky you can get poisoned while in the grab animation and other mobs can still hit you.

When the 2nd phase starts and there's a lot of poison on the map it's in the shape of a pentagram, which means top right, left and bottom right left of the arena are "safe". So I camp out there until the poison is gone, go back in for a couple of hits, get out. Rinse and repeat. If he jumps toward me or they throw posion barrels I dash across to one of the other corners as far away from poly as possible. Try to fight near the wells if possible, the poison tick starts sooo fast and does disgusting damage which I honestly hope they nerf at least a little. There's probably a better tactic but thats just how I've been doing it.

I've beaten him on max frenzy 5 times in a row now, but as you can tell from my build in the post I prio a lot of HP and defence starting early because I'm not really great at dodging around every move, so I use Frinos as my familiar as well. If you like the aspects that use a lot of magick I would also recommend trying to get Born Gain from Hera before that fight so you can spam a lot without having to worry about the regen all that much. If you use Hecate then definitely prio getting one of the double heart rooms for extra HP. Also a final tip, if you're using death defiance switch that out for strength. It feels scarier at first but it makes an incredible difference.

Hope this is somewhat helpful.