During Megatron's return to Earth, Starscream seemed pleased to have him back. He began to question the former's sanity when he began using Dark Energon, once concluding to Soundwave that their leader had become mentally ill. As the two talked upon his reentry onto Earth, Megatron assured him that he would immediately resume leadership of the Decepticons. Starscream was fine with this, asking him for transportation for what he assumed were many warriors he had gathered during his three years in space. Megatron had not met up with anyone during his three-year voyage, but assured him that he would gather some with his recent discovery of Dark Energon.
Following his control of Bumblebee, Megatron viciously attacked Starscream. When the latter transformed and tried to escape his wrath, Megatron grabbed him by the wings of his jet mode and threw him before dragging him off. His damage to Starscream earned him a play on Knock Out's table, where Megatron stated the two had switched roles and would never again do so. Following Starscream's capture at the hands of the Autobots, Megatron scolded Airachnid and had the Vehicons ordered to capture him should he ever return to the Nemesis. Starscream's seeking of redemption was claimed when he won the trust of Megatron after bringing him all four of the Omega Keys, with Megatron reasoning that Starscream was more valuable to him as an ally than as a threat.
Starscream assured Megatron that he would not fail him. Megatron saved Starscream from certain death when he was forced to kill his then-current second-in-command Dreadwing. Following Starscream's thanking, Megatron ordered that he never have him regret which one of the two he spared.
Starscream accompanied Megatron to Cybertron, where the former ordered his injuries to be tended to. Following Megatron's ordering, Starscream dispatched to the skies with the Vehicons. After the Autobot base was destroyed, Starscream exclaimed that the ruins were the place in present tense before Megatron stated that it was no longer.
During the Decepticon invasion of Jasper, Shockwave made an appearance back to the Decepticon ranks, where Starscream seemed to be surprised the most. After Wheeljack escaped from being imprisoned, Shockwave presented Megatron his latest project: a Predacon. This beast was used to hunt the Autobots, but failed as Starscream stated to Megatron that they have no way of knowing why the Predacon had failed, due to it being speechless. When the Autobots invaded Darkmount, the Predacon was bridged to the Arctic where it froze and Megatron was able to overpower Ultra Magnus. Starscream informed Megatron that there was no sign of Optimus Prime. Suddenly, Optimus Prime was flying towards the Decepticon citadel in his new jet pack. The Decepticons escaped from the destruction of Darkmount.
Following Shockwave's latest project, Megatron wanted to use this project to create an army of beasts, despite Starscream's concerns. When the Predacon returned from the Arctic, Starscream was assigned to take command of it by Megatron. Later after the Predacon, or Predaking, revealed its secret, Megatron had no choice to terminate its fellow brethren in Shockwave's lab before they could terminate the Decepticons. Predaking found out from Ratchet that the Decepticons planned his brethren's demise at their hands. Predaking faced against Megatron, but Starscream was able to shoot a cheap shot at Predaking. Megatron opened an airlock to the outside of the warship to shoot Predaking out into the clouds. During their battle over the Omega Lock, Megatron managed to shoot Bumblebee, which killed him and left his lifeless body in the Omega Lock's cybermatter. Megatron was about to finish off Optimus when suddenly Bumblebee, revived by the cybermatter, stabbed Megatron with the Star Saber. Starscream watched in horror as his master's body falls from the Omega Lock down towards Earth. Starscream wanted to avenge his master, but Shockwave told him "Do not be a fool." Starscream replied "Curse you and your logic!"
In Predacons Rising, Skylynx and Darksteel were created by Shockwave in his secret lab on Cybertron. Starscream mentioned that he and Shockwave intended to make an army of Predacons. Their plan failed as Unicron, in Megatron's body, intends to bring back the undead Predacons. Unicron overpowers Skylynx and Darksteel then proceeded with his plan. Starscream escapes, leaving Shockwave to face the zombies, but they seemingly killed him. However, Shockwave somehow survived and convinced Predaking, Skylynx, and Darksteel to help the Autobots defeat Unicron. Optimus Prime returns and defeats Unicron. Megatron was back in his own body. Starscream reminded his master of getting the Decepticons together to conquer Cybertron, but Megatron strongly disagreed with him. After being under Unicron's torture, Megatron has learned the true meaning of oppression and had thus lost his taste for inflicting it on others. Despite Starscream's advice, Megatron said the Decepticons are no more and flies off, presumably exiling himself for his actions.
In Transformers: Robots in Disguise, Starscream holds a grudge on Megatron for torturing him and wants to use the weaponized mini-cons to power up himself to exact his revenge upon his former master Megatron.
Following his killing of Cliffjumper, Starscream was approached by Soundwave, whom played an audio clip of Arcee speaking, thereby alerting him of her presence. Following Megatron's leaving of the ship, Starscream concluded to Soundwave that while their leader was in space, he may have become crazy. Starscream had Soundwave broadcast the battle between Optimus Prime and Skyquake. As Soundwave started to receive life signals from Megatron, Starscream at first ordered him to ignore them until deciding to investigate. During which, Soundwave's drone, Laserbeak, followed him and forced Starscream to report his finding to Soundwave and transport a near-death Megatron to sick bay.
Starscream depends on Soundwave mainly for Groundbridges, but otherwise genuinely loathes him. He also seems to be afraid that Soundwave is listening in on his words, showing his (in this case justifiable) paranoia.
Knock Out (formerly)
Starscream summoned Knock Out aboard the Nemesis to cure their wounded leader after a vote from the Vehicons arose to cure their leader. Starscream was rather surprised at Knock Out's choice of a ground based vehicle form instead of flight. The two appeared to have a stable relationship. Starscream and Knock Out negotiated about ruling the Decepticon cause if Megatron perished from his injuries. However, Megatron was able to resurrect himself by controlling Bumblebee's body and reviving his old body.
When Starscream received a brutal beating from Megatron for nearly attempting to terminate him, Knock Out did his best to heal his comrade's wounds and advised him to rest, Starscream however brushed off about his condition telling him to back off. When the latter had lost his arm Knock Out was keen to give him an upgrade most notable the Null Ray. Starscream refused and was able to get a new arm as a replacement.
In Regeneration, Knock Out happily helped Starscream with placing a new T-cog inside of his body.
In Thirst, after an experiment with Dark Energon on Silas (who was inside Breakdown's corpse) goes into chaos, both Starscream and Knock Out tried to escape the ever-growing zombie infestation on board the warship. They even hid in a room and share their seemingly last moments together by Knock Out complimenting Starscream on his finish and Starscream stating it was an honor to serve Megatron with Knock Out.
In Predacons Rising, Knock Out betrayed Starscream to join the Autobots. Knock Out revealed to Smokescreen and Arcee that if he had stayed with Starscream, he would have been the first to get thrown out of an airlock. Knock Out also points out Starscream was rude for telling him to shut up.
Breakdown is one of rare Decepticons who was an ally to Starscream. Starscream has commanded a rescue mission when Breakdown has captured by the MECH. Then he said him that he must will choose between him and Megatron one day. But it never arrived because Starscream left temporary the Decepticons a little later and Breakdown is killed by Airachnid.
Starscream wanted to extinguish Optimus by sending Skyquake to attack him and Bumblebee. It failed and Starscream still tried to kill Optimus on various occasions. When Optimus lost his memories, Starscream was shocked to see him aboard the Nemesis. Of course Starscream helped the Autobots by telling them about Optimus' current state and telling them the location of the Decepticon space bridge. Starscream was furious at Prime for destroying the Omega Lock in Darkest Hour. Besides his need of trying to terminate Optimus, Starscream sees Optimus as a worthy foe.
Starscream seemed to be very hurt and vengeful when Bumblebee killed Megatron. He even wanted to avenge his master by attacking the latter but Shockwave prevented him from doing so. In Predacons Rising, Starscream and Bumblebee squabble over the Immobilizer until Knock Out intervened to take out Starscream with the device, thus destroying it in the process.
Out of all the Autobots, Starscream was shown to possess an intense hatred and rivalry with Bulkhead. Starscream and Bulkhead also seemed to be the exact opposite of each other, while Bulkhead is huge, strong, slow, and caring. Starscream is small, weak, fast, and uncaring.
In their first encounter in Antarctica, Dreadwing regarded Starscream as a traitor and questioned his loyalty to the Decepticon cause. When Dreadwing found out the latter had desecrated his brother, Skyquake, by raising him from the dead, he attempted to kill Starscream, only to be killed by Megatron on the spot. Starscream was thankful Megatron did not kill him, which Megatron told him to never make him regret sparing his life over Dreadwing's.
Starscream was not surprised to see Smokescreen on their first encounter. When the latter mocked Starscream's height, Starscream seemed to be bothered by his insult.
Arcee and Starscream seemed to relate at first, but when the former eventually discovered Starscream was the one who extinguished Cliffjumper, she had an intense hatred for him, even going as far to execute him if he refused to fight her.
Starscream wanted to make alliances with her in several occasions, however many didn't last long or resulted in betrayal. Starscream developed a hatred for her and told Arcee "what I wouldn't do to get my hands around her wretched throat!" Starscream even fired one of his missiles at Airachnid to save Arcee from being killed by her.
Starscream seemed to see the Predacon as simple, primitive beast who he was tasked to watch. Starscream zapped the Predacon and even insulted it a few occasions. When the Predacon revealed himself as Predaking, Starscream was mostly horrified. In Predacons Rising, Predaking, Skylynx, and Darksteel wanted revenge on Starscream, almost killing him.
Starscream regarded Darksteel as a simple Predacon that he would punish if Darksteel got out of line. He would scold Darksteel on a few occasions but would pay the price when Darksteel, Predaking, and Skylynx wanted to seek vengeance on Starscream, and almost killed him, but Starscream managed to escape.
Skylynx was regarded the same way Starscream viewed Darksteel. He would often scold or punish him if Skylynx was out of line. When Skylynx, Predaking, and Darksteel wanted to seek revenge on Starscream, they went to Darkmount, but failed to terminate Starscream.
Starscream had a deep jealousy and hatred to Shockwave, mainly due to Shockwave being Megatron's lead scientist and viewed highly worthy in Megatron's view. Starscream was caught by Shockwave in an attempt to get Shockwave killed by the Autobots and came close to taking his eye out until Starscream apologized. When Megatron was killed, both Shockwave and Starscream teamed up to create more Predacon clones in Megatron's name. This plan worked as they soon discovered more Predacon bones but failed when Unicron, who took control over Megatron's body, came to resurrect the Predacon graveyard for his undead army. Starscream totally ditched Shockwave and escaped via flight mode. Shockwave managed to survive the attacks from the zombie Predacons.
Starscream was surprised when Unicron used Megatron's body as his vessel. Unicron referred to him as fool and stated Megatron was under his control.