Got one, finished in like 45 minutes, give or take a few.
Definitely the hardest online thus far, but actually really fun considering the floors were random and the battles were tough and needed strategies, it was less run and gun and required more thought and tact.
I could maybe use a more clear idea of where the checkpoints would be though, kept getting super close to death and seriously stressed about whether I’d make it
Ark is really quite good, he reminds me of a fire type version of the water triceratops (name eludes me ATM)
Tips: Dont fight every arks that you encounter. Use escape battle to seek stairs to next floor. I already got the copperhorn with only less than 5 lvl99 monsters and several decent arks on my team. Even you can skip boss at floor 24 which is quite tough and roam till you encounter last boss at floor 28. Last boss quite easy for me. Use checkpoint wisely.