Dezimir

Dezimir is a Quintesson from the Energon Universe portion of the Generation 1 continuity family.

A malevolent Quintesson Prosecutor, Dezimir is a loyal servant of his dark and mysterious master. Unrelenting and cruel, Dezimir possesses many weapons at his disposal, namely a Sharkticon horde and a bestial weapon called Mechanokoar; but perhaps the most deadly of them is a dark antithesis to the Matrix of Leadership wielded by Optimus Prime, giving him the power to enslave anyone unfortunate enough to fall into his grip.

“	Compared to the vastness of the universe with all its mysteries and tortures, you are nothing.	”
—Dezimir to Megatron, Transformers #19

Fiction

Energon Universe

Long ago, Dezimir had Megatron abducted from Moonbase 1. Under orders from his master, Dezimir subjected Megatron to hundreds of trials, going up against hordes of Sharkticons and Dezimir's powerful bestial weapon, Mechanokoar. At the five hundredth trial, Dezimir revealed to Megatron these trials were a lesson in how small the Cybertronian was in the universe and his potential to be more. Revealing the Matrix of Oppression, a "dark equal" to the Matrix of Leadership, Dezimir bestowed it onto Megatron, granting him a third pistol alternate mode that would allow Megatron to override the will of whomever wielded him. Dezimir's master then commanded his subordinate to pick up Megatron and force Dezimir to destroy the Mechanokoar. Transformers #19

After Starscream managed to break free of the Matrix's control, Transformers #24 he swore off using it. Transformers #31 Megatronus began summoning his thrall back into the Matrix, though Megatron believed it was Dezimir. Transformers #26 Transformers #28

Plot details for Transformers (2023) issue 31 follow. Spoilers have expired, you may remove this tag

Eventually calling Megatron back into the Matrix, Transformers #29 Megatronus subjected Megatron to more trials, several of which saw the Decepticon leader fighting copies of Dezimir. Transformers #31