What is glum?

Some articles on glum:

Scooby-Doo! And The Goblin King - Plot
... The Goblin King's two bumbling henchmen, Glob and Glum (voiced by James Belushi and Larry Joe Campbell), attempt to capture Scooby and Shaggy, but they are saved by Jack O'Lantern (voiced by Jay Leno), a living ... King's castle, but they are shot down by Glob and Glum by a goblin gun-like cannon ... themselves as Daphne and Velma in order for Glob and Glum to let them into the castle ...
Jennifer Murphy (comics) - Fictional Character Biography - Second Jennifer Murphy
... Glum ... Glum is constantly trying to kill The Dragon or take over the world, though his plans always come to naught often with comical results ... and hospitalized after an experiment of Glum's caused Angel to grow to gigantic proportions and destroy Jennifer and Dragon's house ...
Savage Dragon - Character Biography - This Savage World
... Glum, who is secretly plotting to kill Dragon ... Glum's plans for world domination were realised using the power of the God Gun (a weapon able to grant three wishes to its user) ... Glum fires the gun and asserts his control of the planet while the Dragon is incapacitated in a hospital, having lost his rapid healing abilities ...

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