Ironhide punching out Starscream when the latter tries to attack Optimus Prime (who was carrying a wounded Bumblebee at the time) in the premiere trailer, thus proving that such heroic nonsense can still make a difference.
And a little after that, Grimlock's transformation. Complete with the ability to shoot fire from his mouth.
We've also got Grimlock and Bruticus going at it until Jazz jumps in. Literally. Jazz jumps onto Bruticus' head. And then the other Dinobots join the fray, with Slug/Slag ramming one of Bruticus' legs hard enough to make him stumble. Then Bruticus gets right back up and backhands Swoop.
It doesn't last too long, but Optimus takes on Megatron, Shockwave and Starscream all at once. He manages to take down Shockwave and then Starscream before Megatron overpowers him. Then Optimus calls in Metroplex.
Some fan service was subtly included in this trailer as well, with Metroplex bridging some more continuity before this video game series and Transformers Prime by referring to Optimus as "the last Prime".
When Metroplex comes in and rescues a captured Optimus by ripping the roof and smashing Megatron with his fist. Best part? You get to control Metroplex and pound Megatron not once, but a grand total of four times into the floor.
The whole scene is awesome. Optimus is dragged to Megatron by the Combaticons. Megatron taunts Optimus, executes a pair of captured Autobot grunts, and begins ranting. Looking out the window, you can see Metroplex sneaking up to the Decepticons, who don't even notice until right as he tears the roof off. That's when the new mission prompt comes up: "Destroy Megatron". WHAM! WHAM! WHAM! CRUNCH! As Metroplex moves his arm away, Optimus turns to the assembled Decepticons and says: "Leave. Now." Behind him, Metroplex is raising his other arm in case he needs to drive the point home.
And it bears extra mention because Metroplex effectively kills Megatron. It takes being rebuilt by Soundwave and an injection of Dark Energon for him to come back. Had nothing been done, he'd have been Killed Off for Real.
Also worth noting, the above mentioned "I wasn't asking" exchange is used here when Optimus is dragged before Megatron. It's every bit as awesome as the version in the trailer, but for a different reason.
And in a mirror of Spotlight: Metroplex, The massive Autobot's target survives the initial assault and has the brass bearings to keep firing.
Grimlock, as promised by the trailers, is walking CMOA. When we finally see him, Shockwave comments about his decreased intelligence which of course causes Starscream to mock him while making an offer to free him. When he gets too close, Grimlock says "I'll free myself!" and grabs Starscream, them throws him at a control panel, disabling his restraints. When playing as him, Grimlock is just as strong in gameplay as the cutscenes make him out to be. Most anything he fights he can easily cut down a couple swings, and in his dino mode even the really strong enemies will die in a couple hits. Big HSQ comes if you use an execution on a giant insecticon, which will have Grimlock biting it in half before tossing it away.
The finale of the game with Optimus and Megatron's fight. The cutscene beforehand has Optimus punch Megatron across what's left of the Ark's bridge. During the fight itself, you get some very cool button pressing sequences:
As Optimus, your first sequence has him pin Megatron against a wall and pummel him before lifting him over his head and tossing him across the room. The second has them deliver a couple punches which ends with Optimus knocking Megatron over with an uppercut when the latter attempts an overhead swing. Optimus then impales Megatron's arm to the ground, grabs him, and repeatedly slams his face into the floor before Megatron fends him off.
As Megatron, the first sequence has him disarm Optimus, slam him into the ground, and hit him until Optimus dazes him with a headbutt and knocks him away before getting his sword back. The second has Megatron punch Optimus and then try to lunge at him, but Optimus dodges, grabs Megatron's sword out of his hand and impales him with it, turning the event in to case of Press X to Not Die as Megatron has to strike Optimus, then knock him away before taking his sword back.
The entire finale itself is just amazing. It shifts between Autobot and Decepticon from different perspectives of the fight until it leads to the epic showdown between Optimus and Megatron. What follows after that is an amazing scene filled with adrenaline rush and nerve-wracking excellence, no doubt thanks in part to the impressive soundtrack that plays alongside it.
Optimus: After eons of conflict, I finally see the truth of your words, Megatron. Megatron: And what might that be, Optimus? Optimus: This universe, no matter how vast, will never be big enough for you and I to coexist!
Grimlock confronting Shockwave at the Space Bridge's controls. Without giving any hint that he knows Grimlock's there, two nodes activate and pin Grimlock down.
Grimlock proceeds to bite off and eat Shockwave's left arm, (Explaining where he got the laser cannon arm from) and then smack him with his tail.
As Bruticus is rampaging on the Ark and smashing through Autobots left and right, the tide of the fight is turned when Jazz enters the fray for a David Versus Goliath-style fight against the giant. The trailer scene of him jumping onto Bruticus and shooting him in the head is exactly what he does.
Though as a point for Bruticus, getting shot over and over again at point-blank range in the face did little more than annoy him.
The best part? As Jazz races in to fight Bruticus- by himself no less- you hear an Autobot claim "Jazz is here! We might finally have a chance!" To explain, Bruticus is a massive gestalt made up of five of the most heavily armed and combat oriented Decepticons, and Jazz- a lone Autobot- is considered an even match.
Jazz and Cliffjumper navigating through the Energon mine. It has Cliffjumper doing some stealth takedowns that would make Batman proud and Jazz pouncing on them with skills that would make Spider-Man proud.
While the Combaticons were always supposed to be impressive soldiers, this game goes even further showing that they're incredibly deadly and effective with or without Bruticus. They're basically the Decepticon Special Forces in this iteration and it shows.
Case in point: When Starscream leads an armada to take down the energon transport, they get slaughtered easily. Onslaught, with only his four boys, manages to do so and salvages half of the energon when previously, they would've walked away with none.
"Combaticons! Combine into Bruticus!"
The ending movie where they break into the bridge and take down everyone standing in their way, with Onslaught's Menacing Stroll towards the control consoles.
Megatron Returns. You start off as Soundwave as you rebuild Megatron. When thats done you take control of the Decepticon leader and personally take over again. This includes fighting all of Starscream's loyalists. When that's done you blast him in tank mode and he flies away.
The best part is that you walk in right during Starscream's coronation. You can guess what dialogue follows.