Balthasar rhymes with:
balthaser, balthaser, balthaser, balthaser, balthaser, curiouser, elsasser, flagofficer, furiouser, kleinsasser, levasseur, officer, purchaser
Balthasar sounds like:
baldassare, baldassari, baldassarre, baltazar, balthaser, balthazar, balthazor, baltzer, blitzer, bloodsucker, blotchier, bulldozer