Main song from Nightvail Team: 
https://www.youtube.com/watch?v=09ULQkTbG88

Original:
https://soundcloud.com/tennobytemusic/tennobyte-fly-away

Tennobyte - Fly Away (Low Pitch)

Not a fan of mashups, but this one is fire and also a Nirvana fan.

NOT MINE, Mashup from AidanTR
https://www.youtube.com/@aidantr

Nirvana Kyouki Mashup (Smells Like Teen Spirit x Creo - Crazy)

NOT MINE, this cracked mashup is from AidanTR on Youtube

This one was swag, anyways, from Nightvail Team
https://www.youtube.com/watch?v=yvqqRfpnE5I

Sounds lot better than original pitch for me

Use -0.1 in Pitch Shifter in Megahack if you want same pitch

Paqoe mashup.

From here: https://www.youtube.com/watch?v=Z0nJ6zouHB8

NOT FROM ME
Original - https://www.youtube.com/watch?v=-AOsw2whZ_o