nice entry, congrats on your first game jam!! the switching between past and present timelines to solve platforming puzzles is a fun mechanic that works perfectly with the theme. i think there is a lot of potential to explore with that mechanic to solve tricky puzzles. one improvement that could be made would be to show the player some kind of indicator which time era they are in with either a specific color or small icon that appears or something. also another place for improvement is to have consistency with the art in your game. for example, the realistic style of the cave and rocks didn't match very well with the minimalist style of the future structures. overall, i had fun playing your game and i think you did a great job finishing your game! Good luck with your future game dev!