Tempo (alter ego Heather Tucker) is a founding member of the terrorist organization known as the Mutant Liberation Front (MLF).

Tempo is a mainstay in the team's adventures, including fighting Wolverine, Sunfire, X-Factor and others in the name of mutant rights, using her time-bending powers.

[1] Soon after, a tyrannical despot named Reignfire reforms the MLF and tasks them with killing Henry Peter Gyrich.

[volume & issue needed] After leaving the MLF, Cable invites Tempo to join X-Force but she declines, choosing instead to go to college and put aside the super-powered lifestyle.

[volume & issue needed] Besides offering her physical protection, Tempo's helmet also contains electronic equipment that provides her with resistance to Cable's telepathic probes.