The Wolfen appears in the Corneria stage. It occasionally fires lasers at the characters on screen. The Wolfen doesn't target any character in particular. Once it has stopped firing, the Wolfen will then fly off the screen after a few seconds. If a character remains on it when it flies off the screen, that character will be Star KO'd.
The Wolfen also appears in the opening movie, piloted by Wolf as he makes his cameo.
The beloved ship of the mercenary team Star Wolf, which was hired to destroy Fox and his team. The ship's abilities rival an Arwing. As a matter of fact, the Wolfen II was an improvement over its predecessor and could nearly outperform team Star Fox's ships. Star Wolf's leader, Wolf O'Donnell is Fox's most persistent rival. (Star Fox 64 06/97)
The Wolfen reappears in the Corneria stage as it did before and also makes an appearance in the Lylat Cruise stage. The Wolfen also appears briefly in both Wolf's On-Screen Appearance in which he ejects from it to enter on the battlefield, as well as a bonus scene of the Subspace Emissary, in which Wolf ejects from the Wolfen and lands on the Lylat Cruise to face off the player (it can be seen here). It's also notable that the Wolfen appears slightly different than the Star Fox: Assault version, where its wings are spread farther apart.
The Wolfen Trophy can be obtained randomly through the Coin Launcher, or other random locations throughout the game.
A class of starfighter piloted by Team Star Fox's rivals, team Star Wolf. Wolfen's boast more gravity-suppressing plates than Arwings, making their performance equal or perhaps even superior. When Team Star Wolf reappeared, they were piloting Wolfen II ships--improved versions with two laser cannons rather than one and capable of reflecting attacks by rolling.