That's to prevent auto-miners from happening.
That's why you shouldnt' leave your computer to mine by itself
Usually you get attacked by rock golems as well, I think
And if you're mining on a heating rock for too long, it'll explode, causing you to destroy your pickaxe, but if you find the head of the pickaxe, you can fix it back together ;D







Just got 45k in 5 mins rofl. Maybe I'm not that stupid.






