While the remaster does have the command '/players X' to act as though X players are in your game for scaling purposes, the console builds do not have access to the chat to use it, only PC. Even with 8 players, level 99 is an unbelievably atrocious grind, and the difference between doing it with 8 and with 1 are massive.

The game scales your XP gains based on how many people are in your game. Second, depending on whether you're just enjoying HC or going for the level 99 achievement. Reopen it, it will resync whatever data the cloud has for you. Because the game was still running, it will also close the game, that's fine now because the save is gone and can't be synced. Go down to the save files, and delete them all, this will only delete your local saves. When you die, without going to the dashboard or closing the game, open your guide, hit Menu on Diablo, and go to Manage Game. Save and quit the entire game (to dash), on a regular basis to make sure your cloud save is as up to date as possible. I don't know if it works to HC cheese in this, but I would assume so, and this is how you would do it. So, if you're going for HC 99, be aware that you need to choose between not being able to save cheese and, for 99.999999999% of the population, not ever being able to reach 99.

Diablo 2 where are characters saved