'Overkill' means to apply or use too much of something, say for instance, use a bomb to kill a spider.
This befits the Mecharus known as Overkill very well, as he takes the most exaggerated and brutal approach to completing his activities, which mainly consist of killing whoever gets in his way.

Overkill, the Terror Tactician

The Terror Tactician,

Heavily-Armored Violent and Tactical Mangler and Bruiser

Overkill initially aligned himself with PentaCorp over the sole condition that he operates exactly how he wants to operate.
[Nanocide: the Mechanomachy]

Later on, Overkill went on to align himself with the Mechavius, on the exact same principle that he gets to kill as many as he wants and do his missions in his way, but on the whole, Overkill will align himself with anybody as long as he can squish, blow up, and brutally execute some puny fleshlings.
[Nanocide: Moth's Rage]

Overkill is a tall Mecharus, standing at around 35 Feet Tall, making him more than a match for his often smaller prey. In his Death Ambulator, he gains 25 Feet and becomes 60 Feet Tall.

Overkill joined under PentaCorp and later COGNITOS on the premise that he could kill as many as he desired, after COGNITOS's fall, Overkill would join the Mechavius on the exact same principle.
[Nanocide: the Mechanomachy and Nanocide: Moth's Rage]

Overkill has 4 known accounts, one named "Knifehole" is a personal account, one that has not uploaded anything, allowing it to avoid getting banned.
Overkill's 2nd Account, named "Assaultus Reviews" is based on QTube, and is all about reviewing weapons like Railguns, Blades, and Grenades, and their 'Killing Potential', this account was getting the ire of many due to moments in which Overkill would encourage the viewer to commit Arson, Murder, and Robbery, but Overkill would eventually purchase a piece of Psycheware from CyberMancer's company, Extraloe. Using multi-layered encryption networks and other built-in functions to make his accounts invincible to getting Terminated, regardless of his activity.
This would help greatly with his 3rd Account "Blowhard's Dying Horribly", hidden in the Deep Net, which shows clips of him slaughtering his victims captured via a camera on his person, this Account mainly gains the hatred of those that view it, with exception of Bleeding Reaver, the sadist scientist, The Victimizer, the sadist arsonist, Vivisectius, the insane vivisectionist, Mutilator, someone who disfigures others for fun, Vindictor, another sadistic thug, Invisor, the invisible assaulter, Salvo, the crazy explosives guy, and many more crazy individuals like them, which doesn't paint the most flattering picture. Either way, this Account is likely used by Overkill to save his most memorable and precious kills to view at a later time, not caring about the reception of others.
Overkill's 4th Account "Book of Caesar" is relatively innocent at first glance, merely being an Account that teaches others of how to do things.
But this conception of his last account would be quickly dispelled once you look into the content, with videos ranging from 'How to effectively use a Blade' to 'How to successfully stage a coup to your Local Government', with all of them attempting to train the viewer to state Terrorist Acts so that Overkill's boredom is satisfied. Many psychotic individuals have claimed that Overkill's videos have helped them in their madness, like Mutilator and The Victimizer, who claim they couldn't have completed their massacre without advice on 'How to detonate inert Military Warheads'.
So, all in all, Overkill's content varies in scope, but all circles around to his favorite topic:
Violence.