I have always loved Lode Runner: The Legend Returns. It had a built-in level editor and I made hundreds of levels as a kid. Unfortunately, it doesn't work very easily on modern computers. However, the people at https://mmr.quarkrobot.com/ have rebuilt the game from scratch, and it's amazing! It runs perfectly, feels the same as the original, and even has some new features (like 4-player capability), particularly in the level editor. And, of course, it's free!
Well anyway, I designed a 40-level set (actually more if you include secret levels) specifically for four players. It is designed around cooperation/coordination, so most levels can't even be finished with less than four, and many require coordinated actions from all four players. I have played through it twice, and implemented some updates with their feedback. Check it out if you (and three others) like cooperative games, puzzle games, and/or Lode Runner!
Download: QUAD SQUAD
Here is a video of one of our playthroughs:
