Avatar
Played this a lot when I was young. Never went anywhere- clearly meant to be an online arena game a la Unreal or Wolfenstein ET or others of its time, but nobody ever played it. Reactive is aptly named- the way literal 'reactions' come into play is unavoidable. Some doors will only open when exposed to hydrogen, but all you have access to is water- you have to figure out what junk to pile together to separate the hydrogen, and it never *felt* like chemistry- just playing around in a goofy, ragdolly, fluid-physics world.And man were those physics were fascinating- one of the first games I knew of that let you climb a wall by rotating your arm repeatedly. Art and audio direction was odd, but there was something profoundly interesting about it all. Like it could have been a classic if people knew more about it.