For anyone doing Tower 100; finally sat down today to try it after an hour on day 1. Took a few different iterations, few million gold in doing full gear swaps for various combos but settled on one that worked pretty solid.
Krau - No mola; ~26k HP w/Aurius, slow - S3 anytime < 16k HP, don't S2
Destina - No mola; 20k HP ~185 speed w/ Idol Cheer, push isera w/ S2 anytime Iseria's S2 is down to cycle faster, other then that heal bot
TAM - Maxxed S2/S3 mola, 16.5k HP ~ i think like 205 speed or something w/ Idol cheer, don't transform unless no other option. Only time I suggest is if last ditch dispel near end
Iseria - + 12 Mola, abit of a werid hybrid build but 214 speed, 55 eff, 100% crit with low 200 crit dam and like 2400 attack i think and 13k HP. Extra damage is nice when its broke but her main goal is to reset Krau's S3 and specific dispels + def break. Ran her w/ Song
Key points to victory;
1) Build 3 focus during first battle
2) Use S1 heal burns on 2 healers as needed, need to pay attention to CR levels etc becaus you want to be getting Krau's S3 out as often as possible especially when Iseria resets are waiting.
3) Don't dispel any buffs with Iseria except Greater Attack, you should be able to handle all other buffs but Greater Attack will most likely wipe you when she is < 50% even with Aurius. If you get resisted on greater attack thats the only time i'd suggest busting out TAM's S3
4) Heals are pretty plentiful so keep pushing Iseria w/ Destina S2 if you need dispel or to get Krau's S3 up.
5) Don't sit on Krau's S3 too long, better to drop 12-15k and cycle then waiting for the 20k+ bombs
6) Be very careful going into < 50%, if bad luck on buffs and she gets speed + greater attack you can get heavily lapped depending on skill rotation she is on and get rolled by her S3 ult
Took me ~ 8-9 trys with above team comp, I had it beat using Rod instead and w/Shim staff and just had horrible RNG on dispels so you don't need double Idol Cheers. I just used a 2nd the extra healing wasn't really doing much and actually pushing Krau to high to often. If def break and high level of focus dont be afraid to burn Iseria's S1...i have max mola in S1 but even with hybrid build debuffed i was hitting for 5-7k at times which is pretty solid.
Had 3 fights in a row < 15% and she got greater attack and iseria with plenty of eff fucing resisted on her dispel so was not a happy camper.
So definitely doable with no ML's and not fully vested mola teams but its a fucking cunt. Not sure how i'd approach it without ML Ten, ML C Armin, Krau, Dark Corv, Iseria as you need some insane burn preferably not on a squishy dps and ability to cycle it. Probably can get a way with replacing TAM/Destina with Lots as a healer for 2nd healer in case you don't have and just push Iseria.
Will see when my wife makes it there on her account (she just hit 95 and was fucking throwing shit lol); she has C.Armin which can help great but not sure who she is going to use as dps since no Krau/ML corv/ML Tene. Lorina has a few unique aspects about her that makes her a good stand in but she doesn't have her up either. I tried to make Cerm work but you can't use S2 without popping a barrier on him.
If they give us future content that doesnt have the stupid not being able to buff crap but similar challenge else where with super high def and no max hp abilities Cerm is going to be a top end damage dealer combined with Iseria. Super cycling Cerm's S2/S3 in combination with greater attack buff, 50% penetration, target + def debuff, and occasional SB has to be top damage rotation in game with equally geared characters on high def targets. Maybe baiken/sigret bleed stacking but can't do much of that when dispels are frequent.
I maxed Cerm's S3 today for future; have her super slow and would run with double idol cheers to keep rotations up. With 4500-5k attack before buffs; i think border coin has potentially to be really useful on her. I have mine at ~ 40.5% attack after 3 uses and its perma which is pretty insane when you stack that + greater attack buff + 50% def pen. Looking forward to getting to use her on new content.
Good luck...thats a bitch fight. Saving my gunther err ML pull for after monday's press conference just incase they give any hints to any tweaks to ML system that they said they are reviewing. Really really would love ML Cecil or Armin on a pull; really struggling to get a consistent def team.