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It's a shame later multiplayer games didn't pick up on the mutator concept. Being able to easily tweak the gameplay mixed it up and added extra challenge or fun.
I recently helped port ioquake3 to the web, complete with UDP multiplayer, and set up an online demo using the internet archive's copy of the Quake III demo: https://thelongestyard.link It would be cool to be able to do the same with Unreal Tournament.
Update, found it: https://www.oldunreal.com/downloads/unreal/full-game-install...