Diablo 4 players can now farm up to four Hellfire Torches with one rotation
A recent hotfix secretly removed the hidden cooldown, letting four players rotate their Coins to farm Uber Tristram and its rewards.
Yes, you can finally farm multiple 
Hellfire Torch in a single Uber Tristram rotation again! This is due to the recent hotfix that apparently removed a hidden loot cooldown that was on the Uber fight. With a group of four, you can take turns using your 
Wirt's Lucky Coins to run the encounter up to four times and collect the rewards.
How to Farm Hellfire Torches With a Four-Player Group
You probably guessed it, but this does involve having 3 other people to play with. To get started, get a group together with four other players that each bring their own Wirt's Lucky Coins. Set the difficulty to Torment 12, then head to Tristram and interact with the fountain.
Make sure only one player activates the fountain at a time, so you do not accidentally lose a Wirt's Lucky Coins or bug it out, because if two players from the same party use their coins at the same time, it can cause issues. After defeating the bosses and collecting the loot, leave the dungeon and have the party leader reset it. The next player can then use their coin to start another run. Repeat this until all four have done it.
More Hellfire Torches, Mythic Charms, and Other Loot
On top of the Hellfire Torch, you will also have an inventory full of Mythic Charms, items, runes, and a ton of crafting materials. You can then salvage the unwanted stuff for more resources and get the most out of your coin this way.
And if you do not have a friend group, you can try finding other players through the local chat, around the fountain in Old Tristram. There are often players looking for groups there. Just make sure everyone has a Wirt's Lucky Coins before starting, and stick with a group you trust. Some players do not have the best intentions, so just be careful who you group up with. Having your own coin ruined because someone leaves in between or things like that is never a good feeling.
Now, if Blizzard could just make those Splinters stackable, farming for the coin would be a little less frustrating.