User blog comment:*mynameischrome*/How to change the text that says "ADMIN" or "CHAT MODERATOR", and how to change the "A wikia contributor" text./@comment-5558012-20150111173038

Edit MediaWiki:User-identity-box-group-sysop and MediaWiki:User-identity-box-group-chatmoderator for the tags. For "A wikia contributor" the most I know that it can be changed is with the RevealAnonIP script.