Well, I've completed 2 levels of the mob grinder. I'm pretty busy with stuff in real life, but I'll get it done soon.

My only issue with this system is the fact that a switch needs to be turned on and off periodically, which means we won't be able to go AFK for prolonged periods of time. Too solve this, I was thinking of using a clock instead of a switch, so the pistons can be turned on and off automatically. What do you guys think of this, and is there the possibility of server lag?