To reproduce this:
- Create a world with the seed '2909526293518662168'.
- Teleport to 1857 60 1891
- See there is a large ocean ruin.
- Dig up and open a few of the outer chests, and see that most of their loot is the exact same. (6 are the same, 2 are the same of different loot)
This kinda makes the loot in the larger ruins very lack-luster, as it's all the same!