Lion were an American rock band, best known for their theme song from the 1986 animated movie The Transformers: The Movie.

A hard rock quartet, Lion (originally named Lyon) were formed in Los Angeles in 1983 after ex-Tytan vocalist Kal Swan (born Norman Swan) and former Lone Star guitarist Tony Smith relocated from Great Britain and teamed up with bassist Alex Campbell and drummer Mark Edwards, who had been in Steeler alongside Yngwie Malmsteen, and Third Stage Alert. After beginning work on a demo, Swan and Edwards recruited guitarist Doug Aldrich and bassist Jerry Best (both of whom had previously recorded with the band Mansfield) to complete the Lion line-up, and in 1984 the group made its recorded debut with "Love Is a Lie", a song on the Friday the 13th Part 4 soundtrack. In 1986, Lion returned with Power Love, a six-song EP released only in Japan, re-issued on CD in 1992 as a 2-on-1 package with Mark Edwards' 1985 Code of Honor solo EP.

After recording the title for the Transformers animated film, they signed to Scotti Brothers and released their first full-length album, 1987's Dangerous Attraction. Their next record, Trouble in Angel City, was released on the Grand Slamm label in 1989. It contained re-recordings of the Power Love EP songs, a cover of the Slade song "Lock Up Your Daughters", and several new tracks.

In September of that year, Edwards suffered a broken neck after falling off a cliff while competing in a motorcycle race. Lion disbanded a month later, with Swan and Aldrich later teaming up in Bad Moon Rising along with former Hericane Alice members Jackie Ramos and Ian Mayo. Aldrich also recorded with Hurricane, House of Lords, Burning Rain, Dio and Whitesnake. Jerry Best would later re-appear in Freak Of Nature, featuring former White Lion vocalist Mike Tramp; he also briefly toured with Dio in the late 1990s.

Source : http://en.wikipedia.org/wiki/Lion_(band)