So there's canon enemy themes for a few enemies in Doom :
Imps have "The Imp's Song" Demons have "Demons On The Prey", "I Sawed The Demons", "The Demons From Adrian's Pen", "Waltz Of The Demons" and "The Demon's Dead". Barons have "Sign Of Evil" Cybers have "Nobody Told Me About Id" The mastermind has "Facing The Spider" "Message For the Archvile" and "The Healer Stalks" are directed at the archvile. Icon Of Sin has "Opening To Hell" Nazis have "Evil Incarnate"
But what about the other enemies? Surely some tracks can fit as their theme, here's my take on it :
Zombies - Running From Evil (An industrial theme that fits as the zombies look like factory workers) Revenant - Bye Bye American Pie (Them bones) Hell Knight - DOOM (A gritty tune to a gritty enemy) Spectre - In The Dark (Mysterious tune for an enemy that fits In The Dark) Mancubus - Shawn's Got The Shotgun (That's the first boss enemy to the tune) Arachnotron - The Dave D. Taylor Blues (I keep on getting equal Nine Inch Nails vibes from the enemy design and the music) Cacodemon - Into Sandy's City (Both are cheerful yet menacing) Pain Elemental - Getting Too Tense (Both give you a sense of urgency) Lost Soul - Donna To The Rescue (The theme sounds naughty and floaty which fits into what the Lost Soul does, the Lost Soul also Outshines the rest of the enemies)