Monster Fighters is a Lego toy theme introduced in May 2012. As of December 2012, ten sets have been released. Seven of the sets contain at least one Moon Stone, and in the background story, the monsters attempt to collect them to unleash doom on the Earth by eclipsing the Sun forever, allowing the land of monsters into the minifigure’s realm. The stones are based on the monster contained in its respective set. A band of Monster Fighters led by Doctor Rodney Rathebone tries to find the stones before the evil Lord Vampyre uses them to eclipse the sun forever.
All the Monster Fighters sets follow a similar pattern. Most feature a lair/vehicle of some sort for a monster with a moonstone somewhere in it and a vehicle for the Monster Fighters. The Swamp Creature contains a swamp boat for Frank Rock, and a small marshy lair for the Swamp Monster. The Mummy includes a chariot drawn by a glow-in-the-dark skeletal horse, and an autogyro piloted by Ann Lee. The Werewolf includes a large brown tree inhabited by the Werewolf, and an old car piloted by Major Quinton Steele. The Vampyre Hearse features, as its name would indicate, a hearse driven by the Zombie Driver.
The Zombies features a tomb inhabited by three zombies, a small podium with a moonstone and a large car driven by Jack McHammer. The majority of The Crazy Scientist and His Monster, consists of a large laboratory, and a small blue car driven by two Monster Fighters. In The Ghost Train, a very large train, with three Ghosts riding on it is featured, as well as a plane driven by Frank Rock. The largest portion of Vampyre Castle is a large castle, although it also includes a car driven by Monster Fighters.
There is no particular colour scheme for the theme, although greys and black are featured prominently in many sets, and every one except for The Swamp Creature and Zombie Coffin Car contains at least one glow-in-the-dark part.
Info courtesy of Brickipedia