Wolf O' Donnel is a villain from the Star Fox series. He is Fox's arch-nemesis. He has his own group, Star Wolf along with fellow shipmates Panther, and Leon.
Super Smash Bros. Brawl
In Super Smash Bros. Brawl, Wolf appears as a playable character, he must be unlocked first. Wolf's Final Smash is the same, his ^B sends him upward which can be directed. His B is an upgraded Blaster, looks like Plasma. His Side B is Fox's. It is unknown what his vB is.
Wolf is actually still greatly rumored. It is not absolutely certain that he is an available character. Some sources confirm him, others deny him. Even still, other sources state that his ^B move "Fire Wolf," does not allow for directional input, stating that "it launches you upward and only upward." This may sound odd, but if it's true, it's compensated according to the source. Wolf, is said to have the side dash move (Wolf Illusion?) similar to Fox/Falco, only Wolf's is said to be a greater distance. His ^B (fire Wolf) is said to be a near instantaneous move, requiring no build up, unlike Fox. In addition, it is said that his ^B sends him further upwards than Fox, but again, without the ability to change direction, thus shooting up and only up. If this is true, it wouldn't be too bad, considering you could ^B then side dash (illusion) to the side, thus returning to the platform. Again, this is one of those characters that has a ton of speculation right now. Until better news comes along we'll have to deal with the speculation.