Board Thread:General Mod Discussion/@comment-25931200-20150420213207/@comment-27723099-20150421011740

2x2 tunnels are unnecessary big. 1x2 is enough and more efficient. The tunnels should be at least 3 blocks from each other (with 2 solid blocks between), though 4 might be more efficient, I'm not sure. I always nine on height 10 to be above lava level.