Origin
The Demon Druid is a somewhat incompetent magician locked in an ongoing conflict with his rival, the Wizard Prang, to prove who is the better sorcerer.
Creation
Wizard Prang and Demon Druid were the stars of Wiz War, an ongoing strip in Odhams Press’ Pow! The strip transferred to Smash! when Pow! was merged into it, and later turned up in a handful of Shiver and Shake Annuals and Whizzer and Chips Annuals.