How in the hell are you supposed to deal with the extreme rate of bosses?

[ReZero Eclipse]

Like, after a point, I'm ending up with several bosses at once because I can't do enough damage to kill them.

Like, it would be doable if there wasn't a shrinking box. Like the box itself is fine but the fact that you get crowded in and ♥♥♥♥♥♥ in the ass is ♥♥♥♥♥♥♥♥.

[Valerie]

Getting better gear makes things easier. I went from struggling to consistently beating the last boss.

[AvG]

Once you start finding some gold items or purples it smooths out quite a bit. It seems the intent though is to encourage you to practice on the first bosses as they are the majority of the loot drop prior to that. Once you have their pattern down you can start killing them each time and it will get easier.
Also don't be afraid to check the shop each time after a run and equip pretty much any weapon. It makes a huge difference even if its a white item.

[Vigilance]

So you got to 7 minutes with the gargoyles, and then being so weak you couldn't kill them you survived another 7 minutes to the necromancer? Without owning the game? Are there other places you can buy it?

You must be talking about Elites, and those only spawn like every few minutes. I'm skeptical that if you're on D0, that you could be so weak that you can't kill any of the elites before the next Elite or boss spawns.

[Cujo]

Dice to control RNG is very nice. All three serve different roles, but I find Alteration, then Banish most useful.

Try out Merris with Warped Shot + Gem High and never look back.

[Handbanana]

The box actually disappears after a while if you don't kill the boss. There are also only 3 bosses in the game right now.

Twins at 7 minutes. Necromancer at 14 and Baron at 20. There are two mini hordes of slimes at 4 and shields at 17 but you should be 1 shotting those enemies.

If you do a bad build and pick bad I guess the green slimes could cause you a problem. Early on.

[Zeel Ara]

It is not possible to see the next boss before the box has dissipated. Hyperbole makes it very hard to take your position seriously. Since we can tell for a fact that you are not accurately describing what is happening we have no way to know which parts are actually true.

[thisTofu]

git gud noob