I've gotten 89% of a single health bar with nefaria but it's extremely slow and difficult.
Try cap america Sam Wilson.
Builds armor and blocks well
Thanks for actually replying with advice instead of just "laugh react"
Omega sentinel is also an option. Gets loads of armors. There is also the wild and crazy idea of the science falcon. Nagase has a video using him. His is duped and R4 but he should still work to chip away at havok. Falcon doesn't get a dex buff so you would never lose the armors you get from parrying with him.
Try to max out Omega Sentinel she's a great option if you can keep up the DOTs
Honestly, I think you'll struggle with that roster unless you are very good.
I don't say that to be harsh and you should try and get as far as you can but keep your expectations reasonable because its not easy with great counters.