Protection - Colossus has a major gamebreaking bug for it as Revenge WILL NOT provide stacks of Colossal Might no matter how many times it hits 3 or more targets.
However there is one fix to this but it costs an additional talent point into Seismic Reverberations.
This is not how it interacts with Arms and Cleave which gains stacks regardless of this talent or not.
Please fix this as soon as possible so Colossus Prot warriors aren’t stuck losing a talent point for something to work properly.