Transformers 1: The Reimagining

The Battle for Hoover Dam

Megatron destroys everything in sight, killing many Sector 7 agents. Firenze is killed by a Sector 7 agent and Megatron transforms into his jet mode and flies away, out of the base.

The humans run to the place where Bumblebee is being kept and see him being electrocuted and tested on. Chip tells them all to stop and Simmons calls them off and Bumblebee takes out his blaster and aims at the Sector 7 scientists.
Chip tells him, "Look Bee, it's me, it's Chip. Look, no one's gonna hurt you, you're safe."
Bumblebee retracts his blaster and is glad to see Spike, Chip and Carly. Spike tells Simmons to lead them to the Allspark.
Bumblebee is in awe of the Allspark and goes to take it. It shrinks into his hands and surge of power goes through him.
"Wow, that was weird."
Hot Rod and Prowl drive to the Sector 7 base having one goal. Find Bumblebee. They race to the base as fast as they can, never stopping for any traffic lights. Bumblebee catches up with them and they rejoice at hearing his voice again and seeing their human friends.
They drive back in Optimus and Ratchet's direction. Bumblebee and the humans tell them about their plan to get rid of the Allspark.
They will take it to an open field to prevent casualties as they ship the Allspark off of Earth.

Megatron flies to the outside of Hoover Dam and transforms, exclaiming, "ALL HAIL MEGATRON!"
Soundwave hears this and repeats to the rest of the decepticons, "ALL HAIL MEGATRON!"
The rest of the decepticons echo this back to him. All except for Starscream.
They all rendezvous where Megatron is and Soundwave kneels down to him. Starscream flies there and Megatron berates him for being late and not punctual. He then goes on to beat Starscream and assures the decepticons, "DECEPTICONS! Know this! There is NO command but mine!"
He lets Starscream go and Megatron asks Soundwave where the Allspark is. Soundwave shows him footage of Laserbeak hovering over Bumblebee, Hot Rod and Prowl.
Megatron makes a menacing grin.

Bumblebee and the others finally find Optimus and Ratchet and Ratchet is ecstatic to hear his voice box is operational.
Hot Rod notices Laserbeak hovering above them and Optimus transforms, taking him down. He then looks straight at the camera and says, "Megatron, I'm coming for you!"
He tells the others to leave and go through with the plan to take away the Allspark. He tells Laserbeak to lead him to Megatron and he does so.

Megatron waits attentively for Optimus as he sees a red semi driving above them. It transforms into Optimus Prime and he stares down the decepticons menacingly. Megatron tells the rest of the decepticons to find the autobots and retrieve the Allspark.
They all drive away and Megatron flies up to him and they stare each other down.
"It has been a long time old friend. I am surprised you are still functioning."
"You shouldn't be."
Optimus dons his energon axe and Megatron takes out his energon mace. They then attack each other in a thrilling battle (taking inspiration from the battle in More Than Meets the Eye and the battle near the finale in season 1 of Transformers Prime). It should last about 5 minutes at most. They then have an exchange about their ideologies with Megatron trying to sway Optimus to his side but he knows once they restore Cybertron, the autobots will be branded as war criminals and executed until extinction.
"HaHaHaHa, you would have made a fine decepticon old friend."
Optimus attacks and Megatron ends up winning their battle and destroys Hoover Dam, flying away. Optimus tries his best to save as many agents as he can as the base floods.