Third stage is just timing on bombs.
Though if everyone's dying from full HP, yeah, you're underlevelled but it's not on the DPS sense—it's survivability.
It's DPS check in the sense that your non-blockers can kill all the tumors that your blockers are stonewalling before they leak. If your people die in one explosion, what you lack isn't DPS check, but both stat check and AoE heal. You need at least two AoE healers (or pseudo-AoE like Myrrh) to deal with the map-wide damage. The rest of the boss' last phase is attrition battle because the boss get inflated defense and resistance, but slowly dying. This is the main reason why the map is a pain: there's a lot of checks at work here.
My operators aren't dying from full health from the boss's Ao E, but in the last phase, they're usually weakened enough from the mobs attacks for the blast to finish them off.
That said, some Ao E medics could help. I have three: Breeze, Ptilopsis, and Perfumer. But out of those, Breeze is only at Lv. 40 and the other two I haven't used at all, and I'm short on both time and resources to raise them up. I might try grinding for them in the event stages to get battle records and LMD at the event store.
One last question. Is it worth it to even try to attack the boss in the first two phases, or should I just worry entirely about the mobs until the final phase? I've made attempts where I have and attempts where I haven't but I've been failing either way.
Update: I just noticed during my afternoon break that the Medic/Defender Chip battles are closed today and I only have 3 Medic Chips and 8 Defender Chips. This complicates matters. Well,this might still be salvageable. If I convert the Defender chips, that'll leave me with 7 Medic chips, enough to E1 a 4* and a 5* Medic. So that would be Perfumer and either Breeze or Ptilopsis. I can grind for The other things I need to get them caught up to the rest of my team, so now it's a matter of whether I have enough time for it.
Edited by Lightblade on Aug 31st 2021 at 2:48:41 PM
In the end, couldn't beat EX-8, but whilst that's half because the stage is hell, I also blame the awful support system (seriously, having to put up with this into anniversary?). Didn't have sufficient Silverash damage/masteries to push it right to stage 3 (and therefore make dealing with the cloaked jerks way simpler), so tried to get the better one on my support list.
For like four hours of various failed attempts. Not once did it show up, no matter how many times I saw the same bloody Exusiai, or the same person's Amiya ffs.
I just wasn't able to defeat the Essence of Evolution and finish the event story. I put a lot of resources into raising up Operators I never used much before, and it still wasn't enough. I would've turned in the event currency to buy things from the event store, but I spent all of it on LMD and battle records to raise Lappland and Perfumer up to the rest of my team for the OD-8 battle.
In happier news, I did a final few pulls on the banners and got two new 5*'s; Croissant and Specter.
I just missed some of the LMD and furniture parts.
If I'd been able to clear EX-8, would probably have farmed out the rest of it.
Oh well, now I just wait, prepare more operators so I can have a relatively easy time for episodes 7 and 8, and look at the Under Tides banner. Well, and whatever gets rerun before then.
I didn't clear out the less rare stuff besides the skill summaries 3 (I'm running out of 1s and 2s to convert) and the LM Ds but did clear out the expensive crap besides the headhunter permits.
I also didn't bother doing the E Xs besides the one for the furniture so I spent the event farming OD-7 for manganese ore. My auto isn't consistent for 8 but then again we're likely to get Twilight rerun eventually so I can farm Grindstones there. Plus, I use manganese ore a whole lot more compared to floor tiles.
I really wished I didn't spend a chunk of my resources trying to do CD-8 with Deepcolor because I ended up not using her. Although it did give me more appreciation for Pinecone.
Edited by terumokou on Sep 1st 2021 at 11:06:15 AM
Burning love!

I don't think i be able to be EX-8 or all the EX challenges.