The visuals are cool, and I liked the style that you're going for. If this is your first jam then getting a 3D horde shooter up and running is definitely something to be proud of. If I was going to recommend something, it would probably be to work with the audio a bit more to create a sense of space. Since the player is standing in a canyon environment there's probably going to be some reverb and echo from the gun shots (you can mess with the reverb and delay effects in Godot's audio buss effects). Also if you don't want to add music then some ambient background noise I think would go a long way from an emersion standpoint. Just some suggestions though, nice job on your first submission