The two main factions of "Transformers" in Beast Wars are descendants of the two main factions in the original cartoon: theMaximalsare the descendants of theAutobotsand thePredaconsare the descendants of theDecepticons. (In the sequel seriesBeast 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 isMegatron, 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 theGolden Diskand Megatron's stolen ship, theDarksyde, which is equipped with a transwarp drive. A Maximal exploration ship, theAxalon, led byOptimus Primal, is sent to stop them. Together the ships plunge through a time/space phenomenon created by the transwarp device during their battle in space, andcrash-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, theAxalondeploys 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 aplot deviceto 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 reptiles, amphibians or invertebrates. Dinobot changes sides, starting as a Predacon and becoming a Maximal, and was later created as an artificial Predacon clone by Megatron in season 3. This made Dinobot the only reptile-based Maximal, as he is based on aUtahraptor. Additionally certain "Predacons" like Inferno andBlackarachniawere 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 fromRattrap, but the Predacons argue and battle for leadership, which impairs their effectiveness against the Maximals.