William Sid Pride is a dashing English gentleman who is fourteenth in line to ascend the British throne. Unfortunately, he's also a fairly two-dimensional character who is focused only on his fiancee, Alicia, who is his wife in later games. In later games, William also appears as the father of Arthur, and he and Alicia have two other children.
William has shoulder-length blond hair and narrow blue eyes. He always wears a formal blue uniform with epaulets and much gold trim. Although he fights with Lord River-n-White in Sonic Wings, William also seems to be friends with Keaton, for he later welcomes the American to his home and offers him an omelet. William is an excellent chef, and Keaton wants to stay at his house for a long time!
In the first game in the series, William's bride-to-be Alicia has been kidnapped by the enemy, and like any stereotypical heroic prince, William sets off to rescue her. He is single-minded in his mission and arguably the most boring character in the game.
In single-player mode, most of William's dialogue deals with his missing fiancée. After the first boss battle, William finds Alicia on the enemy aircraft as it's going down. William "rescues" her by telling her to jump through the air from the moving aircraft into his plane. The brave young lady does so, and the pair lives "happily ever after."
William fights with Lord River-n-White in two-player mode, but there is little difference in the storyline. William says the same things and performs the same rescue at the end; the only difference is the last scene shows his wedding one month later, officiated by River-n-White.
William appears in two cameos in Sonic Wings 2, where he is the father of the baby pilot Arthur. If the player uses Arthur in single-player mode, after the final boss battle, the baby is shown sleeping in Alicia's arms with William looking on. In two-player mode with Arthur and Mecha-Keaton, William greets Keaton and prepares an omelet for him.
William appears in an odd cameo in the Grand Canyon stage. There are several turrets which appear to be naturally occurring but which also attack the player. Most are marked with body parts (eyes, ears, or mouths) and some conceal tanks. However, occasionally, one will crumble to reveal a giant, harmless statue of William's head.
William appears in Special and Limited after the boss battle with Pandora or Gurabura if the player uses Mecha-Keaton and Captain Silver. Recalling the Sonic Wings 2 ending with Arthur and Keaton, the cyborg and Silver go to William's house for food, where Silver, William, and Arthur watch in amazement as Keaton shovels an omelet into his chest.