Bumblebee

Bumblebee is an Autobot warrior and the former scout of Team Prime, as well as the former guardian of his human friend, Raf Esquivel. in Transformers: Prime. Bumblebee was a very important member of Optimus's team during the Great War and was with Optimus for the longest out of any Autobot, excluding Ratchet. Bumblebee went with Optimus, Bulkhead and Ratchet to Earth in an attempt to stop the Decepticons from draining the planet's energy and taking it over. At the end of the war, Bumblebee was the one to kill Megatron, the very same Transformer who took away his voice since the war. However, Megatron was revived by Unicron shortly after, who used his body as a vessel to attack Cybertron. With Optimus missing in action at the time and Ultra Magnus badly wounded, Bumblebee became temporary leader of the Autobots. Optimus returned and defeated Unicron with the help of his team. Before Optimus became one with Primus, Bumblebee promised Optimus that they will keep the peace in his memory before Optimus left. Optimus gave one last smile to them before going into the Core. When the Sparks burst from the Well, the team watched as the sparks fly out to bring life to their home again, including Optimus's own spark.

Years after the war finished, Bumblebee became a high ranking police officer, but was still praised as a war hero, with a partner police cadet Strongarm, but he began to see visions of Optimus leading him back to Earth with Strongarm, street punk Sideswipe and Mini-Con Fixit where they discover a crashed Decepticon ship with numerous fugitives at large. A dinobot named Grimlock, who was a prisoner on the ship, teams up with them as well as humans Denny Clay and his son Russell. Bumblebee takes leadership in his new team to hunt down the Decepticon fugitives on Earth. On some occasions, Bumblebee would mess up on his battle cries, which would make his team laugh or not impressed. In Battlegrounds, Part 2, after Bumblebee and his team, along with a revived Optimus Prime, seemingly defeated Megatronus, Bumblebee found a phrase that impressed everyone.

Bio
Bumblebee was born as one of the last generation to be created from the Well of Allsparks after it had ceased producing life. During 'The Great War', Bumblebee joined the Autobots where he fought alongside Optimus Prime and several other comrades during the centuries-old skirmish.

At an unknown point, Bumblebee took part in an operation to track down Overload, a Decepticon spy whom had managed to destroy a selection of Autobot installations. Bumblebee attempted to apprehend him, tragically however he was brutally overpowered by the physically-superior Decepticon; however, Overload was eventually captured by his leader, Optimus and placed into stasis.

At some point during the war, Bumblebee was captured by Decepticon forces at Tyger Pax, upon where he was brutally interrogated by Megatron though the young scout valiantly refused to reveal any information which ultimately resulted in the Decepticon leader destroying his voice box  and was subsequently left to die. However Bumblebee was later discovered by Autobot troops and was evacuated to a triage facility where he was stabilized by a field medic Ratchet where he was able to communicate (via beeps and tones), though was unable to repair his voice box and thus was rendered mute.

After Arcee had been captured and interrogated by Arachnid, immediately after the death of Tailgate, Bumblebee, alongside Cliffjumper, managed to invade her personal lair and managed to save Arcee and escort her to safety.

After the near conclusion of the war which had ultimately reduced Cybertron to become uninhabitable, Bumblebee personally joined Team Prime alongside Optimus, Ratchet (and presumably where he met Bulkhead) and thus evacuated the planet via The Ark. Together they traveled across the galaxy for thousands of years until they eventually reached Earth.