da3dsoul

This is a very easily reproduced bug that I, and several of my friends, have gotten. If you have certain mods that are either cheap, buggy, or just don't go well in certain worlds, it is common to remove them for a world. The other circumstance is the most common. Minecraft updated, and it's a really cool update, but not all of my mods are updated. I'll just take out the less useful one that doesn't get updated quickly. Load old world. Now the block ID's are completely mismatched for all mods. Bauxite is now Creative Energy Cell, and Twilight Forest is made of Maceraters. Forge very well remembers the block ID's if the mods don't change, but as soon as one is added or removed, everything is jumbled. I have tested this with the same version Minecraft and forge and removed one mod. In this case, it was Additional-Buildcraft-Objects. It does the same with any mod that adds blocks or items, so that part is irrelevant. The two joking examples I gave were not jokes. Bauxite (AvP) has been replaced by Creative Energy Cell (TE4), and Twilight Oak (Twilight Forest) has been replaced by Macerator (IC2). If I put the mod back, all the blocks disappear into air, and the items are replaced as original. The blocks would probably go back to original if they weren't always replaced by TileEntities, but I use a lot of mods that have TileEntities.