[09:44:51] [Server thread/INFO]: Saving chunks for level 'New World'/Overworld
[09:44:51] [Server thread/ERROR] [FML]: A TileEntity type majgenrelativity.forcelasers.tileEntities.ion_Tank_Tile_Entity has throw an exception trying to write state. It will not persist. Report this to the mod author
java.lang.RuntimeException: class majgenrelativity.forcelasers.tileEntities.ion_Tank_Tile_Entity is missing a mapping! This is a bug!
	at net.minecraft.tileentity.TileEntity.writeToNBT(TileEntity.java:93) ~[TileEntity.class:?]
	at majgenrelativity.forcelasers.tileEntities.ion_Tank_Tile_Entity.writeToNBT(ion_Tank_Tile_Entity.java:32) ~[ion_Tank_Tile_Entity.class:?]
	at net.minecraft.world.chunk.storage.AnvilChunkLoader.writeChunkToNBT(AnvilChunkLoader.java:410) [AnvilChunkLoader.class:?]
	at net.minecraft.world.chunk.storage.AnvilChunkLoader.saveChunk(AnvilChunkLoader.java:193) [AnvilChunkLoader.class:?]
	at net.minecraft.world.gen.ChunkProviderServer.saveChunkData(ChunkProviderServer.java:266) [ChunkProviderServer.class:?]
	at net.minecraft.world.gen.ChunkProviderServer.saveChunks(ChunkProviderServer.java:332) [ChunkProviderServer.class:?]
	at net.minecraft.world.WorldServer.saveAllChunks(WorldServer.java:976) [WorldServer.class:?]
	at net.minecraft.server.MinecraftServer.saveAllWorlds(MinecraftServer.java:419) [MinecraftServer.class:?]
	at net.minecraft.server.integrated.IntegratedServer.tick(IntegratedServer.java:147) [IntegratedServer.class:?]
	at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:540) [MinecraftServer.class:?]
	at java.lang.Thread.run(Unknown Source) [?:1.8.0_31]
[09:44:51] [Server thread/INFO]: Saving chunks for level 'New World'/Nether
[09:44:51] [Server thread/INFO]: Saving chunks for level 'New World'/The End