Premise
The two main factions of "Transformers" in Beast Wars are descendants of the two main factions in the original cartoon: the Maximals are the descendants of the Autobots and the Predacons are the descendants of the Decepticons. (In the sequel series Beast Machines, the process during which Autobots and Decepticons became Maximals and Predacons is referred to as "The Great Upgrade".)
The leader of the Predacon team is Megatron, a namesake of the original Decepticon commander. He and his forces are a splinter group on the hunt for powerful crystals known as energon. They do this with the aid of an artifact known as the Golden Disk and Megatron's stolen ship, the Darksyde, which is equipped with a transwarp drive. A Maximal exploration ship, the Axalon, led by Optimus Primal, is sent to stop them. Together the ships plunge through a spacetime phenomenon created by the transwarp device during their battle in space, and crash-land on a mysterious planet.
The planet is found to be rich in deposits of raw energon, in such extreme amounts that it proves to be poisonous to both factions' robot forms, forcing them to take on alternate organic forms for protection until their robot forms are needed. Thus the robots take on the beast forms of recognizable animals including mammals, birds, fish, reptiles, amphibians, dinosaurs, and invertebrates.
Before crashing, the Axalon deploys its cargo of "stasis pods" containing Maximal protoforms — Transformer robots with vulnerable and undeveloped physical forms, which are left to orbit the planet as an alternative to possible destruction in the initial crash landing. This plays a larger part in the IDW series, The Gathering. Throughout the series, stasis pods lose altitude and crash-land on the planet, and the Maximals and Predacons race and fight to acquire them, as protoforms acquired by Megatron's forces can be reprogrammed to become Predacons. The stasis pods are used as a plot device to introduce new characters.
The teams are divided between the "good" Maximals and the "evil" Predacons, equivalent to the traditional Autobots and Decepticons. Most of the Maximals are based on mammals, birds or fish, while the Predacons are based on arthropods and dinosaurs. Dinobot changes sides, starting as a Predacon and becoming a Maximal, and was later recreated as an artificial Predacon clone by Megatron in season 3. Additionally certain "Predacons" like Inferno and Blackarachnia were created from Maximal protoforms, but were fitted with Predacon shell programs, fighting instead for the Predacons. For the Maximals, the emphasis is on team spirit and good-natured arguing, especially from Rattrap, but the Predacons argue and battle for leadership, which impairs their effectiveness against the Maximals.
