In Knock Out's lab, Starscream bemoans his current situation, having to compete with Shockwave for Megatron's favor. His whining is interrupted much to his annoyance by moans from Cylas, who is strapped to a table and begging to be freed by Starscream. Knock Out injects Cylas with a derivative of the Synthetic Energon he recovered from the Autobots. The compound drives Cylas into a rage, which Knock Out notes is one of its erratic side effects. Starscream sees in Cylas's fury the makings of a super-soldier for Megatron.
Starscream attempts to inform Megatron of this discovery, but the Decepticon leader is only interested in discussing the status of the Predacon Protoforms with Shockwave, who is reporting in from his off-site lab. Brushed off by his leader as unimportant, Starscream sulks on his way back to Knock Out's lab.
Cylas becomes more enraged with each new injection of Synth En and his eye glows green. Knock Out discovers that the more the compound is administered, the faster Cylas burns through his own natural energon reserves. Starscream cannot see the use of having another unruly beast that can't be controlled, but then has an idea: Dark Energon. Knock Out objects, noting that the "Blood of Unicron" once turned their own ship against them. Starscream assures the doctor that a controlled, minimal injection will merely place Cylas under Megatron's command, via their leader's symbiotic link with the substance while also saying that "super-soldiers" are a military concern and thus, the project falls under his supervision, not Shockwave's.
Under orders and under protest, Knock Out injects Cylas with Dark Energon. Cylas temporarily powers down before rebooting in a rage with his eye glowing purple and breaking free from his bonds. But after only a few steps, he crumbles to his knees, desperately low on energon. Starscream expresses irritation, which prompts Knock Out to remind him that the Synth En formula causes the user to burn through their Energon reserves faster. This leads Starscream to suggest that they withhold further infusions to allow Cylas to calm down a bit. Then with a fierce roar, his upper teeth become fangs and his lower jaw splits into monstrous mandibles that have veins of Dark Energon on the inside and a long, bladed proboscis emerges. He attacks, snapping Knock Out's prod and sending Starscream and Knock Out fleeing down the halls of the ship.
Once a safe distance away, Knock Out suggests sounding the alarm. Starscream disagrees, not wanting Megatron to learn of their actions. He claims that once Cylas attempts to feed upon the ship's highly trained Vehicon troopers, they will take care of the threat.
Elsewhere, one of the Vehicons stumbles upon Cylas, who grabs the highly trained trooper and begins draining his energon.
Starscream and Knock Out plan the disposal of Cylas's corpse when they find the Vehicon's corpse instead. While the two argue about who's to blame for their predicament, the dead Vehicon rises as a reanimated Terrorcon and reveals the same segmented jaw and bladed proboscis that Cylas had causing both Knock Out and Starscream to scream in terror. Starscream's blaster fire only staggers it, and Knock Out's suggests destroying the Terrorcon's head as he have seen human horror films...at drive-in theaters. Though Starscream's missile is successful in decapitating the creature, it doesn't stop it in the least, as the body lumbers forward with the proboscis sticking out of the neck-hole. A concentrated volley of blasts to the Vehicon's chest destroys the monster's revitalized spark, severing its link to the Dark Energon.
Knock Out posits that Cylas could infect the entire crew in the same manner, a theory that's borne out when they find themselves pursued by multiple energy-draining Terrorcons. Starscream and Knock Out lock themselves in a comm room to get a breather and assess the situation. Accepting that this may be the end, the two Decepticons exchange final pleasantries and step back into the hall…right into Megatron, who angrily demands to know why the Dark Energon in his spark has been acting funny. Starscream provides a slanted explanation, but Megatron doesn't believe it until he's forced to destroy an attacking Terrorcon.
After a more extensive debrief of the situation, Megatron puts the ship on high alert and orders Starscream and Knock Out to destroy Cylas. Around the ship, Vehicons and Insecticons battle the infected Terrorcons.
Cylas wanders into the ship's vault snarling and repeating the word Energon over and over. Sensing energon within a stasis pod, he breaks it open, freeing and reviving Airachnid. Cylas attempts to drain her energon, but Airachnid is able to immobilize him with webbing long enough to deliver a killing blow. She immediately re-establishes her telepathic control over the Insecticons and commands them to return to her. Their sudden departure is noticed by Soundwave.
Starscream and Knock Out discover Cylas' corpse. Starscream is elated until Knock Out points out Airachnid's destroyed prison, followed by Megatron demanding a status update and when Starscream tells him that he had both good news and bad news prompting Megatron to scream in rage.
Airachnid leads the Insecticons through the halls of the ship, ordering them to wipe out every Decepticon aboard. At the end of the hall, Soundwave calmly steps forward to face them. The bug-bots attack, and Soundwave opens a Space Bridge directly in front of him at the last second. Before they can react, Airachnid and the Insecticons are teleported away. As the bridge closes behind her, Airachnid realizes that they have been sent to a moon orbiting the abandoned Cybertron and screams in rage.
Aboard the Nemesis, Megatron contacts Shockwave again to inform him they're implementing his containment protocol to prevent further outbreak. He also tells Shockwave to speed up the Predacon cloning project, as they have now lost more than half their military forces. Knock Out is sternly reminded that he is the ship's medic under Shockwave's command, and is forced to turn over all of his experimental projects to the scientist. Megatron then turns to Starscream, intent on teaching him a lesson the only way that seems to get through to him...
Back on the moon, Airachnid instructs the Insecticons to "Serve their Queen." She suddenly reveals that she is infected and quickly drains the energon from one of her minions as the rest of the Insecticons line up obediently to await their turn.
- Knock Out discusses the events of "Stronger, Faster" and "Flying Mind" with Starscream, even though Starscream wasn't part of the Decepticon ranks when either took place. While it is conceivable that Starscream learned of the events of both episodes through the ship's logs or another source, Knock Out speaks as if they were both witness to them.
- Airachnid lost one of her spider legs to the closing pod door when she was put in stasis, but all six are intact in this episode.
- Starscream's missile cleanly beheads a Vehicon, leaving no burn marks or exposed circuitry of any kind. For that matter, the headless Vehicon reveals that there is no "joint" on the model for the head to attach to, just a completely flat surface with a hole for the tongue. You normally don't see it because the neck just goes straight into the base of the collar, as if the collar form-fits around the neck.
- This is the first episode which doesn't feature the Autobots in any capacity. Previously, "Patch," the last Decepticon-centric episode, had flashbacks which contained Autobots even though none appeared in person. However, it is worth noting that the Vehicon that appears behind Megatron is voiced by Peter Cullen, who voices the Autobot Leader, Optimus Prime.
- On-the-move teleportation seems as if it's becoming Soundwave's signature move, having used it to dispatch Arcee in "Orion Pax, Part 1" and to claim the Predacon fossil in "Project Predacon."
- Megatron alludes to the beatings he bestowed on Starscream in "Darkness Rising, Part 4" and in-between the episodes "Out of His Head" and "Shadowzone" when he prepares to punish Starscream "the only way he understands."
- Starscream and Knock Out's little scene of accepting their near end is similar to Optimus and Arcee's scene in Scrapheap. Only difference was that they were dealing with zombies and Optimus and Arcee were trapped in the Arctic.
- The Synthetic-Dark Energon mutagen created by Starscream and Knock Out in this episode shares several similarities with the Reaper Strain from Blade II. Both turn the chief non-human species of the series into rabid, primal bloodsuckers which are driven to infect others and suck their blood/Energon with a fanged proboscis. The Energon mutagen and the Reaper Strain are also both artificially created by the enemy by accident and proceed to become a deadly epidemic among the antagonist faction's ranks.
- Starscream says that if Predaking got infected there would be no stopping him. This is proven in Predacons Rising where nothing stops the undead Predacons until their master is imprisoned.
- On that note, where was Predaking when this hit the fan?
- This is probably one of the most mature episodes in the show, certainly not for children, especially for someone who is watching this for the first time.
- The storm that surrounds the Nemesis is actually justifiable in this episode, given its dark plot.
- Megatron calls Cylas the "Plague Bringer", this may be a possible reference to the Black Death which was brought upon by rats biting humans, killing thousands and depopulating Europe. This is what happens in this episode, aside from the fact the Black Death did not cause their victims to become undead.
- Starscream's actions in this episode cost the Decepticons the war, as the plague results in the speed up of Project Predacon, which is called off when Predaking reveals his sentience. This results in the construction of the Omega Lock which brings Racthet to the warship, which results in Predaking going on a rampage, which allows the Autobots to storm the warship and kill Megatron.
- This episode has several similarities to the G1 episode "Dweller in the Depths" The Quintessons intented to use the Dweller to drain the power out of every Transformer similar to Starscream's plan to turn Cylas into a soldier that Megatron can control. The Dweller went on a rampage, draining the power from anyone in its path using its tentacles and nets, similar to the probosices that the Terrorcons use. Both are defeated, but at a cost. The Dweller is launched into space with the new Power Core, and the terrorcons are defeated. The Autobots must wait for several episodes for their new power core to be built, and the Decepticons lose more than half their strength. Starscream is beaten by Megatron and the Quintessons are presumably killed by the Dweller when it latches onto their ship.
- Megatron tells Starscream that "You have been awarded more chances for redemption than anyone in Decepticon history!". This implies that he regrets killing Dreadwing, as Starscream has caused a number of errors in Season 3 so far in attempts to please him. Dreadwing was only given one chance to stand down before being terminated.
- On that note, the fans assumed that Dreadwing would become a Terrecon and attack Starscream, but his body wasn't in the warship. This raises the question of what happened to it, though it is entirely possible they disposed the body in a secret manner or placed Dreadwing's body in a tomb.
- It is possible that the Dark Energon injection revived Breakdown and rendered Cylas's control obsolete. This is possible as whenever we hear the husk's voice, it resembles Breakdown, with Cylas not even speaking until he is killed.
- Breakdown's body is dstroyed again.
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