It kind of sucks right now. There's like 6-10 floors per stage and you randomly encounter enemies on the way. You need to do like 140 stages in 1 run to clear it, more if you reset. If they made it so you can save progress and start other quests like dailies it would be fine. It could probably use an auto button since all the enemies are trash tier for a long time player, but I'd be fine if they just let mesave and do my fucking acc quests.