In preparation for 1.13 some blocks\items need to be split out into their own Ids. This will make the transition to 1.13 easier however it will remove items from a player's world as there is not a good way to convert metadata blocks\items to the new blocks\items.

A new branch will be created for 1.12 so anything going to 1.12.2 can still be done before the flattening. The Master Branch will be post-flattening and be mod version 1.3.1.XX.