|Voiced by||Alan Oppenheimer|
He is by all accounts a nasty, evil ghost with a dominating personality. He sometimes makes an extremely harsh electrical static sound while he speaks. Prime Evil tends to be petty and unforgiving and has no tolerance for failure with his underlings. He is also known for creatively punishing said ghostly minions' failures in delightfully karmic ways. For example, in "The Headless Horseman Caper," Fangster receives Vampire Fleas for his failure. At other times, though, he'll simply zap them to a pile of dust.
Prime Evil looks like a cyborg version of Skeletor in flowing, scarlet robes. He has a Jacob's Ladder in lieu of actual teeth; it sparks when he's especially angry.
Several episodes depict Prime as being nothing more than a robe with head and arms attached!
He drove Jake Kong family to close a mine they had(from episode "The Headless Horseman Caper"). Prime Evil's first encounter with the Ghostbusters happened as the Senior Ghostbusters were training the next Ghostbusters in the mine. Prime Evil ended up trapped in the mines locked vault 100 years along with Brat-a-rat. However, he eventually managed to get out after lying to Belfry by telling him he was a trapped bat.
Prime Evil is described in Our Buddy Fuddy as one of the greatest wizards who ever lived, second only to Merlin. His powers are indeed great; in most episodes he's completely immune to the Ghost Dematerializer. He's even shown to have the power to rematerialize his henchmen who've been affected by the weapon, although he often chooses to delay doing this out of sheer spite.
- In the original concept sketches, Prime Evil was designed as a more traditional Grim Reaper-type figure, or at least strongly inspired by Mumm-Ra from Thundercats.
- Prime Evil has an overbearing sister named Prime Ordeal (Who calls him "Itchy") and a bratty nephew, whom his sister only refers to as "Snookums".