stcelestine said: Have you considered changing 'he or she' on cards to 'they'? E.g. 'Target player puts the top card of their library into their graveyard.' Singular 'they' is perfectly acceptable English, it would be less awkward to fit in the text box, and not exclude non-binary people.
Perfectly acceptable English is a little inaccurate. There is debate among the professional editing world whether or not the singular “they” is acceptable English. The style house used by Wizards (I believe it’s the Chicago Manual of Style but I’m not an editor so I could have that wrong), for instance, currently does not support the use of singular “they”.