So I found a fun bug to abuse. When you have prepared ceramic mold in the forge - you take single clay mold and left-click with it on a ceramic one in the forge - you get your ceramic mold and clay one takes its place in the forge, BUT! It instantly becomes ceramic after that. And procedure can be repeated infinite amount of times. Works in SMP too. Addendum: Works with beef too. If you substitute cooked beef with raw one. Seems to be a major issue. Can anyone confirm it's not just me? Another addendum: Checked that it's not configs or other mods. Also - works only if you have coal under that slot. Scratch that, works only with freshly cooked stuff (meaning in current session or maybe current chunk update). Still - a bug nonetheless. Bug still works in B73. Also tested on glass.