This is how Sentinel Prime's betrayal goes in My Little Pony Transformers: Dark of the Moon.
[Ironhide and Rainbow Dash are under attack]
Twilight Sparkle: Ironhide, protect Rainbow Dash, get her inside.
Ironhide: Consider it done.
Twilight Sparkle: [to Moon Dancer and Captain Thunderbolt] Look, we also have to get Sentinel to safety. Cause he's the key to the pillars.
Sentinel Prime: Indeed I am. What you must realized, my Autobot brothers is we were never going to win the war. For the sake of our planet's survival, a deal had to be made...with Megatron.
[Sentinel fires at Ironhide twice]
Captain Thunderbolt: Get back!
Ironhide: What have you done?
Sentinel Prime: I hereby discharge you from duty.
[Sentinel fires at Ironhide before he falls to the ground]
[Soldiers, guards, the Autobots, Mane 6, Spike, Starlight, Trixie, Discord, Thorax, and the Canterlot warriors fall back as Sentinel fires at them]
Rarity: Bee!
Captain Thunderbolt: Get back!
[Bumblebee returns fire]
[Moon Dancer and Adagio return fire]
[Sentinel fires at the soldiers before driving off]
[Sentinel goes inside]
Captain Thunderbolt: Rally all PHOENIX forces back to the base!
[As Sentinel heads into the base to retrieve the pillars, Rainbow Dash uses her friendship magic on the dying Ironhide, removing his cosmic rust]
Major Malfunction: I've got him. Help the others.
Rainbow Dash: But who's gonna repair the damage.
Major Malfunction: Two of my students.
[He shapeshifts into Brawl and hauls Ironhide away]
[Inside, Celestia is approaching when Sentinel blasts a few vehicles]
[Celestia and her guards run for cover]
[Sentinel destroys some vehicles]
Princess Celestia: Hey, Sentinel, what is going on? What do you think you're doing?
[He stops for a moment]
Sentinel Prime: I'm a Prime! I do not take orders from you!
[Thunderbolt and his squad arrive]
Captain Thunderbolt: Move! Move! Move!
[Sentinel continues his attack]
Sentinel Prime: Now, return what belongs to me! [destroys more vehicles]
[More ponies try to get away as Sentinel drives away with the pillars]
[Optimus drives up and transforms to robot mode and looks around in shock and sadness]
Princess Celestia: Yeah, take a look around, Optimus! This is all on you!
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