Underwater Ruins can be generated in the sides of ravines
Underwater Ruins can generate in the sides of underwater ravines. I assume the game is spawning it at the very edge of the ravine floor, causing it to be in the wall. This leaves no opening from the top, which also conceals the chest.
An example of this can be found on the seed -5384628059105572773 at (310,25,-235)
2018-03-08, 09:29 PM
2018-06-18, 10:40 PM
2018-04-03, 02:13 PM
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