The end world is crashing on DragonControllerLandedFlame.
I attempted to clear out the end crystals with MCEdit, but that didn't solve anything.
[10:24:15] [Server thread/INFO]: Scanning for legacy world dragon fight... [10:24:15] [Server thread/INFO]: Found that the dragon has been killed in this world already. [10:24:15] [Server thread/INFO]: Found that there's a dragon still alive (EntityEnderDragon['Ender Dragon'/2754, l='MCTX_Anarchy_the_end', x=0.48, y=74.30, z=0.36])
There is no generated crash report.