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Um here is a reason why Calyrex-Shadow should be banned . Just give it Tapu lele support and it eliminates the real issue in Calyrex-Shadow is No priority with psychic terrain there is no priority.
Any priority is disaster for calyrex-sh
Yavaltal is a pretty decent mon in of it self and without dynamax Calyrex-sh is Shit and gets hard-walled by yaveltal unless it has a +3 up in which case you are fu*ked