[22:55:57] [Client thread/INFO] [STDERR]: [net.tynkyn.common.TYNKYN:preInit:908]: Severe error, please report this to the mod author. (Potions)
[22:55:57] [Client thread/INFO] [STDERR]: [net.tynkyn.common.TYNKYN:preInit:909]: java.lang.ArrayIndexOutOfBoundsException
Maybe related to this: https://github.com/Thaumic-Tinkerer/ThaumicTinkerer/issues/493
Thanks. I followed the link and downloaded the file. As far as I can tell, the error seems to be with Thaumic Tinkerer. Can you try taking Thaumic Tinkerer out and see if the same error happens?