Master Blaster is the forty-ninth episode of the Beast Wars TV series.
Silverbolt dutifully patrols the Maximals' fortified entrance to Mount St. Hilary, unaware that the Predacons are building something sinister in places unknown. Megatron, trying another attack on the Maximals' base, sends newly promoted sub-commander Waspinator with a large explosive (from…somewhere) to destroy the patrolling Fuzor. Waspinator delivers the missile and destroys Silverbolt's gunning turret, and when Optimus Primal, Cheetor, and Rattrap rush outside to defend their home, Waspinator commands a full attack. Alas, the plan was only a feint to draw out Primal, and without support from additional troops, Waspinator is quickly crushed by the Maximal leader.
Hiding out of Optimus Primal's sight, Tarantulas blows a dart that burrows itself into Primal's foot, crawls through the Maximal leader's interior machinery, and accesses Primal's own spark. Primal disregards the infection, tells Cheetor to "take a rest" with a suspiciously Western drawl, and punches out the young Maximal.
Blackarachnia returns to the Maximal base, surprised by the open doors. She finds the entire interior dark. Primal sneaks up on the arachnid, and when she reveals that Depth Charge isn't with her, he grabs her as if she were a toy. With the widow restrained, Megatron and his cronies step out of the darkness. Quickstrike is revealed to be controlling Optimus Primal by piloting a large, mechanical suit of similar form to Primal's body. The other Maximals are being kept deactivated in a hanging cage. Megatron instructs Dinobot to find-and destroy-Depth Charge, assigns Inferno to watch over the imprisoned Maximals, and allows Rampage to "take care" of Blackarachnia. With that done, Megatron orders Quickstrike and the puppeteered Optimus Primal to follow him; the Ark awaits!
In front of the Autobot starship, Megatron orders Quickstrike to download the access codes to him-the process fails, however, as the codes now require a Maximal spark signature to be used. This barely fazes Megatron, as he simply has Quickstrike use Optimus Primal to open the door instead. Megatron walks through the halls of the ship to find what he's looking for: his namesake, the original Megatron. The Predacon leader opens his own chest, and a tentacle reaches out of it to access the spark of his predecessor. After a bit of struggle, Megatron takes the spark into his body, and immediately collapses. While his "boss" convulses from the pain of containing two sparks, Quickstrike dumps his leader into one of the lava pits outside, giving the Ark to his real superior: Tarantulas!
In the depths of the Maximal base, Rampage gleefully torments Blackarachnia, but the she-spider overpowers the massive Transmetal crab by using telekinesis to knock him down with a steel girder. Thus freed, Blackarachnia sneaks through the base, then leads Inferno away from the Maximals he's supposed to be protecting and locks him outside so she can free her team (and blast Inferno with the autoguns).
Quickstrike gives Tarantulas access to Teletraan I. Tarantulas then sends Quickstrike away to destroy the Maximals while he rigs the Ark to explode, which will kill all Autobots and Decepticons within it. As Tarantulas leaves the Ark, Megatron emerges from the lava, now reconfigured into a dragon form by his plunge into the molten rock and the additional spark within him. Megatron burns the spider who betrayed him and tosses Tarantulas into a distant lava pool as punishment for failing.
Quickstrike, still piloting his armor, finds Blackarachnia and double-teams her using Optimus Primal's body, which is still under his control. But with a well-placed blast, she causes the two giants to fall over each other. The fall frees Optimus, who remembers what he did under Quickstrike's control, and he and Blackarachnia head back into the Ark to prevent the devastation.
Megatron finds Optimus Primal, and the two enhanced transformers battle. While Blackarachnia tries to save the Ark, Megatron shows off his new abilities against his most hated enemy. Blackarachnia saves the Ark with just a single second to spare. Optimus is then saved from Megatron by the combined firepower of the other Maximals, who force Megatron to retreat. But with the spark of the original Megatron still in his possession, Megatron has gained a new advantage in the Beast Wars.