Sentinel Prime (Movieverse)/Bio & Battles

"The needs of the many outweigh the needs of the few..."

- Sentinel Prime

Sentinel Prime is a very patriotic individual, believing that all Cybertronians are Gods. He is a member of the Dynasty of Primes. He was Optimus Prime's mentor, who taught him every thing he knew. Before he left Cybertron in the Ark, he handed leadership of the Autobots to Optimus Prime. He was famous for being a proud and feared warrior on the battle fields of Cybertron, using a double-bladed Primax Blade and a shield-changable Cosmic Rust Gun with great skillfulness.

Sentinel Prime left Cybertron near the end of the war. Though it was believed that the space bridge technology he designed was to turn the tide of the war, Sentinel Prime actually sided with Megatron to rebuild Cybertron by finding an inhabitable world and enslave its occupants, if there were any. However, the Ark, Sentinel's ship was hit and it eventually crashed on Earth's moon in 1961. As part of their plan, the Decepticons proceeded to steal hundreds of pillars from the ship, leaving Sentinel and five pillars, including the Control Pillar behind as only Sentinel could use the pillars and he was in stasis lock from lack of energon. After an engine part from the Ark is found on Earth, Optimus Prime and Ratchet travel to the moon in the Xantium and retrieve Sentinel from the ships hold, Ratchet scans him and tells Optimus: "His levels are faint." They also find 5 space bridge pillars. They put Sentinel in the Xantium and return to Earth.

Back at the NEST base, Optimus uses the Matrix of Leadership to revive Sentinel who attacks him at first out of confusion before calming down. Sentinel asks what has happened to his pillars, and Optimus tells him that they only found 5, upsetting Sentinel. He and Optimus proceed to explain the pillars functions and the threat they pose if the Decepticons get them to the humans. Sentinel is also unimpressed with Charlotte Mearing and her condescending tone towards him. Optimus takes Sentinel, now with a Rosenbauer fire truck alt-mode, on a drive to see the planet. Sentinel is impressed with the planet, comparing it to Cybertron before it was devastated by war. Optimus laments what could've happened if Sentinel led the final battle of the war instead of him. Optimus offers Sentinel the Matrix of Leadership, but Sentinel refuses it, saying that Optimus is now the teacher rather than him. After Sam Witwicky learns of the Decepticons plot, he, Bumblebee, Dino and Sideswipe escort Sentinel back to base chased by the Dreads to protect Sentinel. Along the way, Dino and Bumblebee kill one of the Dreads and Ironhide shows up to kill the other two with the help of Sideswipe. Once at the base, Sentinel reveals his true colors, and explains his betrayal to the humans and Autobots for he's agree an deal with Megatron and Decepticons and murders Ironhide with his Cosmic Rust Gun and retrieves the pillars, telling Mearing that he doesn't answer to her before fleeing.

At the National Mall, Sentinel opens a space bridge to the moon to bring in an invasion force of Decepticons and Optimus pleads with him to stop. Sentinel refuses and Optimus attacks him, but Sentinel proves to be too strong for Optimus. Sentinel pins Optimus down and explains that he's doing this for the sake of Cybertron and that one day Optimus will understand. Sentinel tells Optimus that Optimus is lucky he didn't kill him and leaves. Sentinel proceeds to send a message to the UN claiming that he's only after some of Earth's natural resources (in reality its human population too) and demands the exiling of the Autobots which leads to their apparent destruction on the Xantium at the hands of Starscream.

In Chicago, Sentinel meets up with Megatron on top of the Hotchkiss-Gould building where he sets up the space bridge pillars and activates them to bring Cybertron to Earth. Megatron is excited that they will save Cybertron together before Sentinel angrily tells Megatron that he's working with Megatron and not for him. Sentinel stays out of the fighting as Cybertron starts to arrive until Optimus uses Shockwave's cannon to shoot down the Control Pillar, temporarily deactivating it.

From the TF wiki