Let me fill you in on this one XD
In Minecraft (C) there are certain blocks that observe proper gravity.
Most you can stack right out the side of others hovering over the ground and they will just stay there, not Sand though, oh NO, that crap has to fall! However it doesn't fall when the map first builds the terrain, no it hovers till you do something like, I dunno, say dig a piece, then ALL the sand touching that piece that is hovering comes CRASHING down.
In this case i saw a huge cave that was probably 5 stories deep, I figured I'd dig straight down to the floor then investigate, this is what happened, dig, SHIT, boom, half my heath GONE! X3
<<< PREV | FIRST | NEXT >>>