your mainly going to want to search for Dungeons for the Skeleton spawner but i'm afraid to say that the ratio for finding a Skeleton one is pretty poor
Here are the chances of certain mob spawners in Dungeon's
i wanted to find it close to my house for an Xp/bone farm, so I went into my mine and after 5 minutes of searching I hear skeletons I dig a few blocks and hey wouldn't you know a skeleton spawner not even far from me at all:)
nice. glad to hear it worked out for you. i'm lucky to have 3 spawners near my house, ones a Zombie and 2 are spider's, shame the 3rd wasn't a Skeleton
The easiest place to find spawners is the desert. Get on a hill and look around spawners near the surface will look like a dug out square and you should be able to see some cobble.
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