But there is a story behind this little scene . First this was created on 1 . 10 . 2 using the official 1 . 10 . 2 release of RFTools and McJtyLib the versions that are now in Infinity , DW 20 and so on . Then I replaced McJtyLib and RFTools with the versions that I compiled on 1 . 11 using CompatLayer . I also added the 1 . 10 version of CompatLayer . The world still loaded and worked . But we are still on 1 . 10 . 2 . Then I migrated the world itself to 1 . 11 and replaced the 1 . 10 . 2 version of CompatLayer with the 1 . 11 version . McjtyLib and RFTools didn ' t change . What you see here is the end result . Everything mostly still working fine . The spawner on the right still has an issue but I was expecting that . Actually if you look closely you ' ll see a white spawn egg in my inventory . That was a cow spawn egg which apparently also lost its information during the transition . I will release these updated versions in a moment