This is really fun! Gives me mega nostalgia for old DOS games like Tank Wars. Music is super catchy too!
The sounds and music are indeed nice.
I only noticed due to this comment that the game is supposed to have sound as it wasn't working on my machine. There seems to be a problem with Godot 3 and PulseAudio on Linux. I had to change the setting for Output Latency from 0 to 30 in the Godot project file to make it work.