Minecraft – How to get into a gold dungeon in the aether

When a chunk is populated, the dungeon generation is always tried 8 times independently at random positions in the chunk. For each generation, given a random size (5x5, 5x7, or 7x7, excluding walls), a dungeon is generated only if the ceiling and floor blocks are solid and there are 1~5 air blocks in the lower half of the surrounding walls.

Possibility? That's complicated to calculate because the probability distribution of air blocks is more complicated and that depends on this. However, you can certainly qualitatively assert that double dungeon is rare. I assert the existence of triple dungeon.

What I do is stand where the spawner is, and find which corner moving to causes both the X and Z coordinates to decrease. This is the corner that should be four blocks from the spawner. (Likewise, when both coordinates are increasing you should move three blocks out from the spawner.)