Riodan doesn't get anger often. He's much more prone to sadness or worry. As a result he does get, Anger Born of Worry - TV Tropes The most common tell he has is, Fist of Rage - TV Tropes

The most usual result of his anger is he gets super determined and he will make what needs to happen. Negative extremes that can happen are, Suddenly Shouting - TV Tropes ...

and a one or two item Anger Montage - TV Tropes and it's mostly to be items that are related to the anger even by proxy.