Early '90s animation tools were so primitive that Doom's lead artist says he pretty much did the whole thing…
Doom's lead artist Adrian Carmack revealed that he used the undo key in Deluxe Paint as his primary animation tool for the original game. Due to primitive tools and frame limitations imposed by John Carmack, Adrian Carmack developed a method of cycling through frames using undo/redo to create animations for enemies and weapons.
PC Gamer
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