The second player uses only a gamepad, while the first player uses the keyboard and mouse. Unfortunately, I didn't have enough time during the game jam to implement online multiplayer or add visualization of falling rocks and weapon upgrades. However, these are great ideas for future updates ! Thank you for your suggestions and your interest in the game. I would really appreciate it if you could try it out and give me your feedback ! For my part, I plan to try your game this evening !