I feel a bit creepy when alone in base and the theme music start playing
also i like the beat off left 4 dead music more or use it replace Horde event in game for more thrilling
Some sound link
https://youtu.be/DKPxRC9sdrM
https://youtu.be/E1O4wAxN_nU
https://youtu.be/dfAn_Kz6Sh4
https://youtu.be/l_wnRaN6SKA