Depth Charge

"Raw energon, right through your twisted spark! Take it! Take it straight to the pit, you sickening piece of slag!!"

~Depth Charge's final words before killing Rampage and himself.
Depth Charge was a transmetal Maximal who served in the Beast Wars in season 3. He joins the maximals because his archnemesis, Rampage was working for the Predacons. He crash landed on Prehistoric Earth to find Rampage, who he calls by his original name, "X", and took the form of a Manta Ray. When Dinobot died several episodes earlier, Depth Charge took his role in being the stubborn, surly but powerful Maximal and also constantly butting heads with Rattrap.

Depth Charge was once a prison guard on the colony Omicron and Rampage was a prisoner there. Rampage escaped and killed several guards, many of whom were close friends to Depth Charge and destroyed the colony making Depth Charge the only survivor. Depth Charge became a bounty hunter and searched for Rampage and after 4 years, he captured him and brought him to Cybertron. Depth Charge asked for permission from the Maximal High Council to personally execute Rampage but was denied. The council decided to leave Rampage in Optimus Primal's care for scientific studies which led to the events of Rampage's episode debut. Depth Charge became furious, blamed Optimus and tried to follow the Axalon but was able to find the wormhole bringing him back in time til 2 seasons later.

When he encountered Rampage on Earth, both were evenly matched and when Optimus asked for allegiance from him, he refused but he would help them if Rampage was involved in the attacks. He can detect Rampage and can smell his spark. When Megatron created the clone Dinobot II, he used a piece of Rampage's spark to which Depth Charge could detect both predacons and made it a priority to wipe out both. For the remainder of the season, he assisted mainly Cheetor and Rattrap in missions and began trusting his allies a little more.

In part 1 of the two part finale, Depth Charge and Silverbolt searched for the homeless Predacons through the air and when they found them, Depth Charge disobeyed Optimus' order to wait for backup and set to engage. Depth Charge found a hole that the Preds went into but booby-trapped it and it injured Silverbolt. Optimus, Depth Charge and Tigerhawk discover that Megatron, Dinobot and Rampage have located the Nemesis, the great Decepticon warship and are in the process of acquiring it and could win the war. With the ship deep underwater, Optimus told Depth Charge to get there first and try to destroy it to which he agrees and Optimus and the other Maximals would be their backup. When Depth Charge found the ship, Rampage was waiting for him and the two engaged in one final battle. With hundreds of uncut energon that were unaffected by the quantum explosion, both Transmetals used them for swords and dueled to the death. Depth Charge had the advantage as he sliced Rampage's chest to have him reveal his spark and tried to stab his spark. Knowing his fate, Rampage allowed Depth Charge to give the final blow and let out one maniacal laugh. Depth Charge had completed his lifelong mission but it cost him his life and caused an explosion. Optimus arrived and believed that the explosion was the Nemesis destroyed by Depth Charge but then he saw both Depth Charge and Rampage's parts floating and realized that Depth Charge had payed the ultimate price. By destroying Rampage though, the evil in his spark in Dinobot was destroyed which made Dinobot good and helped the Maximals destroy the nemesis.