I have my incineration rune on grog. I've been using him all the time since his epic came out and Winter fest is meaning a lot of dungeons. I have never seen him burn anyone with burning touch. I started counting the number of attacks where he didn't kill anyone and didn't set them on fire. I stopped just under 270. Piggy set all sorts of people on fire, or showed the "burn immune" caption.
Has anyone seen this work? At least lately?