Phoenix Mustangs
The Phoenix Mustangs were an expansion franchise in the WCHL in 1997, essentially trying to fill the void of the Phoenix Roadrunners of the IHL, who had ceased operations. However, the reason the Roadrunners did that was because the Phoenix Coyotes of the NHL started up in the desert in 1996.
Playing out of the Arizona Veterans Memorial Coliseum, the Mustangs made the playoffs each of their first three seasons in the league, and won the league title in 1999-2000! Amazingly, they won that title while have an under .500 regular season record (31-35-0-0-6). That team featured minor league scoring legend Hugo Belanger. If you're not familiar, Belanger never played in the NHL but amassed over 500 goals and 1465 points over 15 minor league seasons in the 1990s and 2000s.
After registering a losing record in 2000-01 and missing the playoffs, the Mustangs were unable to secure a lease for the 2001-02 season, and were forced to cease operations.