Overt-Kill used to be known as Nicholas Rocca in Sicily. At age 13 he was already a thug running an extortion racket to local businesses and even offering himself as a leg breaker for the mob. Soon he became one and was hired by a mob boss named Luciano to kill the son of another mob boss. After getting murdered by hired guns, he was rebuilt into a human cyborg killing-machine, now hired by Tony Twist to kill Spawn.
Tony Daniels only did grunts for Overtkill, so he unfortunately cannot be eligible for this voice compare.
Jamie Hanes does this take that immediately resonates well with the "rebuilt man to machine Robocop/Android 16" type character, sounding very chilling and threatening. Wish Jamie did more roles, but I'll take his Overtkill and Violator.
J.S. Gilbert voiced Overtkill in the Game Boy Color game, and such a great casting choice really didn't work out well for this take. He sounds super growly and more like a demon than a killer cyborg without any subtly that he is indeed the bad guy in his delivery. Yes yes, he voiced Astaroth, but that voice here just isn't as effective as Jamie.