My ideal would be having toggles like they currently do to set reactions as ‘active’, if they’re off or you’re out of resources you get no pop-up. If you can react, something pops up on your screen and you have three seconds to Y/N it before it disappears. You literally have you react to the reaction prompt or you lose it. That wouldn’t slow the game down much, if at all and would allow so many more reactions, like Absorb Elements, using Featherfall the way it is meant to etc
