When Mirror!Optimus offers Cliffjumper the opportunity to execute Rumble in the smelting pool. While unwise, Cliffjumper's attempt to talk some sense into Optimus comes across as rather heartwarming, especially from a confessed Decepticon hater.
Cliffjumper: You know I despise the Cons' more than most but we can't just destroy him like this for entertainment! It goes against everything we stand for, what you stand for. I can't believe I'm the one telling you this! This isn't justice Prime, it's murder! This isn't how we do things! I'm sayin' you need to stop this!
What makes it really good though is the fact that up to that point, Cliffjumper still wasn't a hundred percent sure he trusted these Mirror Universe Decepticons. But after witnessing Megatron putting himself in danger for a stranger (not unlike his Optimus Prime) Cliff is finally convinced which side is in the right.
Despite his overprotective nature, Starscream respecting Sephie's wish to be her own hero.
At the end of "Invasion", after leaving their old universe behind as it self-destructs thanks to Ultra Magnus. Heroic Autobot's, Deception's and even evil Decepticon's all are left horrified over what's just happened. Straxus steps up and suggests that not all hope is lost.
After a particularly costly battle, Optimus, Brawn, Prowl, Ratchet and Inferno are all tossed out of Sky Lynx by Rodimus, much like the battle that caused Prime's death and Megatron's reformatting in the original universe's movie. They do indeed stumble across Unicron... But thanks to the efforts of Nexus Prime mostly wiping out the concept of multiversal singularities, this Unicron has developed a mind based on the remaining mercy and good will he had. Thus, when he reformats the group into Nexus Prime and the Knights of Unicron, he does so telling them their mission is to stop Rodimus and end the war. And since Primus in this universe has only ever influenced the world in a positive way as well, this ultimately leads to the end of the cybertronian war for the SG universe, as not only do Nova Prime and Galvatron reconcile and swear to lead their people to an era of peace and happiness, but this universe's Unicron and Primus are both benevolent entities that are unlikely to rekindle or perpetuate it.