For Jack-O-Lantern, I used Medusa. Once I had a ton of fury stacks, one SP2 cleared 3-4 bars with bleed damage thanks to deep wounds.
For Squirrel Girl, I used Wolverine (Weapon X)
For Vox, I used Kushala.
For the last few rounds, the Captain America IW fight (I've tried Crossbones, Kingpin, Aegon and Black Cat) and Morningstar have been kind of a bust. With Morningstar being completely unblockable unless you intercept and get a cool down of 10 seconds, that fight seems a bit rigged to me, and the Captain America fight, most attacks glance off.
I haven't tried Silver Samurai yet.
It's still a fun challenge but could use some fine tuning a little bit if this is going to be a permanent feature.
Apparently my comment was saved as a draft but never posted, so I have to write it out again.
Medusa for Jack-O-Lantern, with enough stacked furies SP2 does massive damage Onslaught or Weapon X for Squirrel Girl Kushala for Vox, she cleaned his clock Captain America IW was a challenge, I didn't have much luck here with any rotation of skill champions. I tried Crossbones, Kingpin, Aegon and Black Cat without much success and the attacks that do land, most glanced off. Morningstar was also a bit of a challenge with her being passively unblockable. Cap IW and Morningstar seem a bit rigged to me but maybe I just need more time to practice. I have not started Silver Samurai level yet.
this method with Idoom is the way. I cleared 80 bars with this rotation
for Morningstar, even with the Unblockble (which I kept forgetting to do INITIAL attack right away), but afterward, just keep pushing her to SP1.
You don't need to worry about the Unblockable if you keep letting her do SP1 (doesnβt matter, can stay away from it).
Only occasionally, if after my own SP's if she will not reach her own SP before my combo would end, I would end my combo short, retreat, and intercept right back again.
But otherwise didn't really care that she was unblockable most times. Your own SP's and Striker attacks should be able to keep her on SP1 pretty much all the time.