Beast Machines was an animated television series. It was a direct sequel to Beast Wars taking place within the continuity of the original Transformers series.
Season 1 Rise and Fall: 13 episodes (1999)
Season 1 largely centers on the Maximals' efforts to find out what has happened to them, as they arrive on Cybertron with no memories. In addition to Megatron and the core Maximal cast, three new Vehicon generals are introduced, as well as the new Maximal Nightscream.
Season 2 Battle for the Spark: 13 episodes (2000)
The ultimate face-off at the end of Season 1 is resolved in a most unusual and cerebral manner, setting the tone for Season 2 as Primal realizes his mission is one of balance, not extremism. Silverbolt rejoins the Maximal ranks, a new Maximal arrives from off-world, and two dangerous new generals join Megatron's side as the Maximals search for the lost Sparks of their brethren and battle to regain control of Cybertron.