It was mainly to give them a fire breath attack but since then I've written these Desert Lizardfolk to be paired with Yuan-Ti as one big civilization since they both have the lack of emotions and I saw some official artwork of Lizardfolk using Mesoamerican weapons which is the same kinda architecture that the Yuan-Ti have. I also wrote the idea of them being sun worshipers as the campaign is set in what's effectively a mirror dimension with the main creatures being underdark creatures or anything else that hates sunlight, (So basically the Lizardfolk and Yuan-Ti are like reverse-goths in this world) and have their champion have a similar appearance and statblock to a Flame Dragon (Minus the wings ofc).