Board Thread:General Discussion/@comment-27033632-20160215163310/@comment-679780-20160215194539

In Sonic Heroes, the three character types do sort of have a rock-paper-scissors relation. Power Types have an advantage over Speed Type, but a disadvantage over Fly types.

However Knuckle shimself also has some control over the power of chaos from being the guardian of the Master Emerald. He holds some wisdom over Chaos Emeralds himself so perhaps he would have some advantage over Shadow.

It's still rather hard to tell since Shadow can perhaps out-stradegy Knuckles, use Chaos Control and does have an array of skills that make Shadow lean a bit towards being Power type, just as Rouge is a "Fly" type despite having same Sonic Adventure movesets as Knuckles.