Patches is a mini-boss in Elden Ring that can be turned into a merchant based on one's actions.
He resides in Murkwater Cave but won't show himself until his chest is looted in the boss chamber. However, once he's knocked down to half health, he'll ask for mercy, in which case one can spare him or kill him. If allowed to live, he'll remark on becoming a merchant and for you to visit him later. True to his word, he'll have stuff to sell on the next visit, calling his business Patches' Emporium.
He'll also have yet another closed chest that you can ask him about but he'll just note he waiting for that special customer for it. On a second visit you can ask him again about it and he'll decide to give it to you for being such a special customer. However, opening it will teleport you to east Limgrave, more specifically very close to a Lesser Runebear scratching up a tree. That said, you're also placed very close to the pillar where the East Limgrave map is given.
Eventually he'll remark he plans to move on from the cave, though he'll leave the rest of the gang to continue running things.
After you slay Praetor Rykard, Patches leaves the manor and can be found next at the Shaded Castle, where he hands you the Dancer's Castenets. You can give it to Tanith, but she will simply ignore it. Patches then moves back to the Murkwater Cave, where you can fight him a second time and get his gesture.
- If allowed to live, he'll reveal that he's also a Tarnished but managed to get by for a time by showing his ways of survival to the local knights.
- Patches can also be summoned during the fight with Starscourge Radahn, but he will almost immediately return to his world after receiving damage.