Several published adventures that I intend to use in my Frost-Bitten Lands campaign (http://www.autarch.co/forums/actual-play/my-acks-campaign-setting-frost-...), such as Skull Mountain and Sinister Secret of Saltmarch, have Lizardmen as a major ingredient. However, I'm not sure if these lizardmen - the natural inhabitants of warm swamps - would fit my frozen campaign.
So which creature should replace them? Kobolds (which are warm-blooded)? Human cultists? Warm-blooded lizardmen (ala theropods)?