Demon's Souls 4-2, the cliffs of the Shrine of Storms.
Particularly one spot where the flying Mantas are too numerous and too far away to effectively kill, and the game seems to go: "Boy I sure hope you picked up and understand how valuable the Thief Ring is or else this part is gonna suck."
You are trapped on a narrow cliff facing three silver skeletons, one archer and two melee, all while being barraged with death spikes from the sky. Dodging runs the risk of sending you off the edge, the mix of constant heavy melee and ranged bombardment makes blocking difficult, even if you get the chance to attack you run the risk of being interrupted at any moment and just taking a single swing too many will cause your character to slip right off the edge.
You can lure the Skeletons to a small ledge which they cannot get up and shoot them to death. It is made incredibly tedious still though depending on how good your bow is and being forced to stop every other shot to dodge more flying death spikes.
Then after you kill the silver skeletons? Two Gold Skeletons with massive swords! Granted you have a somewhat more spacious area to lure them to. You still have to deal with the Mantas shooting at you.
Even for a game like Demon's Souls this is a spot where the odds are simply too greatly against you.