Evil dragon Valacirca from The Faraway Paladin anime. Definitely one of my favorite dragons. Not just for the cool design, but his interaction/dialogue with Will was a lot of fun to watch. I wouldn't put it past him to tease heroes in 'certain' ways for kicks.
Illustrious v1.0
Trigger: valac1rca
Reinforcement: solo, dragon, feral, hi res, scales, scalie, horn, wings, membranous wings, one eye closed, scar across eye, teeth
Strength: 0.8-1 (Lower strength is better for flexibility in posing/backgrounds, but sacrifices some of the finer character specific details)
Optional: one eye closed, scar across eye
SD 1.5
You can get some passable results with a little elbow grease. Version A (YM4)is best. Version B (YM5)was made with regularization images. B is not as good at producing the specific character traits, but general dragon anatomy is a bit better. I had some good results combining the two versions in various ways,usually with version A dominant. Check the example prompts for some ideas. Didn't have much luck with getting good eyes or the eye scar.
Trained using Yiffymix3.6.
Main trigger: valacirca
Optional: eye scar