You can get through the fence next to the altar.

OK

Without him, it would be a detour

This thing is useless, according to the literature, if you want to get it, jump down from the mountain, and wait for the second round to pick it up with a fast character.

Jump off the roof

jump down

Go up to the roof and turn left. There are two remote mobs there. Clear out the one with its back to you, then go to the end and jump down.