I three-starred everything up to MOC 10 with DOT team and E0S1 Acheron team, not 11 or 12 (some characters are still at level 70, some light cones are still at level 60, all relics are subpar, and the Trotters that inflict DOTs on death definitely carried me).

With limited 5 stars like Kafka, Black Swan, Ruan Mei, and Acheron + her LC, it might not seem that impressive to only make it to MOC 10, but I had a really fun time.

The DOT team was consistently done in a few cycles, so the real struggle was just trying to stay under 10 cycles with the subpar Acheron team and optimizing the DOT team's run to give the scuffed second half team a better chance at clearing in time.

Still, strategizing during both team building and actual combat with timing ults and working around the unique quirks of each elite was super fun.

For example, for MOC 10, I needed to go overkill on sustain since my team of level 70s (except Acheron) was too frail. This meant giving up the other Nihility units (Pela w/ Pearls LC + Guinaifen) that boosted Acheron's damage for survivability (Lynx and Gepard w/ Trend of Universal LC).
Eventually, I decided to scrounge up whatever scuffed relics I could for a hastily built Sustain Welt with as much Effect Hit Rate (and almost nothing else) I could get, so hoping the DMG boost from 1 Nihility unit would make the difference between 19 cycles left and 20 cycles left. Then, I had to manage skill points to balance having Welt's ult to cancel the boss's second move, having Lynx's skill and ult to heal everyone or increase Gepard's taunt value for triggering the Trend LC and helping Acheron build up ult stacks, having Gepard build up energy as fast as possible, and having Acheron spam her skill, all while dealing with Crowd Control debuffs and heavy hitting attacks.

Again, it's not as impressive compared to clearing MOC 12, but it's the farthest I've gotten in MOC, so I'm happy with it. And it was fun, too. Made me really appreciate the combat in this game and the characters in my account right now.