The giant holes are from me looking for desert. My traveling was a bit eradicate. Also the giant snow area on the top of the picture was also from me.
Looking closer at the map, that small hole in the bottom of the map isn't there. It's really a small lake and some mountain.
Anyways, for those who have portals and monsters turned on. Beware, Ghasts can spawn in any 5x5x5 spaces around portals. Which means they can spawn outside of hell.
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