Tabitha Smith is a fictional character, a comic book superhero in the Marvel Comics universe. Created by Jim Shooter and Al Milgrom, the character first appeared in Secret Wars II #5 (November 1985). She later appeared as a member of the X-Force and, more recently, as a member of Nextwave. Since her first appearance, Tabitha has used a number of different codenames, including Time Bomb, Boom-Boom, Boomer, and Meltdown. Tabitha is one of the mutants to have kept her powers after the 2005 "House of M" storyline.