SVG animations are a lot of fun. I really like this puzzlehunt puzzle that makes use of them: https://2021.teammatehunt.com/puzzles/time-of-your-life https://20

SVG animations are a lot of fun. I really like this puzzlehunt puzzle that makes use of them: https://2021.teammatehunt.com/puzzles/time-of-your-life https://2021.teammatehunt.com/puzzles/time-of-your-life (fair warning: puzzlehunt puzzles tend to be essentially unsolvable if you aren't familiar with the conventions of how they work. this one is no exception. there is a link to the solution at the top)