Thanks.
The sounds were taken from a CC0 pack and pitch shifted, but they reminded me so much of Quake that I had to use them.
Yeah, about the difficulty, unfortunately it was WAY harder until right before I submitted, then I did a quick rebalancing pass, because games that are too hard are usually a no no in jams. Moved the pedestals, made explorers slower, decreased the max number of simultaneous explorers and made so this number increases with time (every 30 seconds I add one more, up to 12). Every few seconds a door will try to spawn an explorer but it might fail, so the pattern might seem random but it really isn't as you noticed.
Anyway, plenty of lessons learned. One of the most important one was to learn to compromise, because I came very close to not submitting the game.
Again, thank you for playing.