There are a bunch of rules, I'll cover the gist of it but I'm sure to miss something. Also there are variations.
Starting at level 1 clear every map, kill every monster once, complete every quest.
Here's the catch.
No gear from other characters. You can only start with your class default starting gear. You cannot TP except where it is required by quests. You cannot go back to town except where it is required by quests. You cannot buy anything from vendors. You cannot repair anything at vendors. You cannot clear any area multiple times to farm for gear or grind for levels. You can only use items that drop from chests and monsters. You can use runewords, but good luck getting them without farming. You can use quest rewards such as Charsi imbue or Larzuk socket, but must use them immediately with the gear you have, no saving the reward for later.
Ideally this is on hardcore with a group and only one of each class. When someone dies, they are out. You work together to try and beat the game with one life each. If you kill Hell Baal, then you go for Hell Cow King. If you complete that, then you are allowed multiple runs (still no vendors) to grind for keys. Once you have your keys you attempt Ubers with the original rules.
RackAnewShoe
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