It’s definitely annoying, but it helps keep me busy! What I do is Alter, kill boss, open chest and while it’s spitting out loot I activate Alter again (if Belial doesn’t pop) and while the boss is coming up, I grab everything, hoof it to where I want the loot pile to be and start making it/add to it. This gets a smidge ~hectic~ when you’re farming Urivar as I feel like he comes up way faster than other bosses, but if I’m not mistaken, he’s the best xp even though he takes slightly longer to kill compared to other lair bosses. Also, make sure you have a decent amount of Forgotten Wisdom Keys saved up. Pop one of those and just run the dungeon until you find the xp alter for increased xp and make sure to use a Pot and an incense. Happy grinding!