Ah the theremin, it's the musician's cheat code for spooky ambience (you must have been frustrated not to have any in musescore)
I made it myself because I didn't have any sound in my banks.
You're the second person to tell me it sounds like a secret boss. Funny. I didn't think of it as a final confrontation but as a lieutenant or secondary boss, which is probably why.
Anyway, thanks for your comment, it's always heartwarming. I know you take the time to listen in detail to my music and that makes me happy.
PS: I haven't taken the time to comment on everyone either.