Actually It's Commander Tartar's Theme

Actually it's Commander Tartar's Theme is a song from the Octo Expansion.

Description
This song is played in a cutscene where the Telephone introduces itself as Commander Tartar and declares its plan to destroy and recreate all life on Earth with the NILS Statue.

It starts with a vocal with some effects applied. Then, slowed-down demonic noises play alongside said distorted vocal.

In-game, there's an extra part that's not heard on the Octotune version, consisting of repeated vocal intro and percussions.

Telephone's Theme
The vocal intro of the Telephone's Theme is sampled into this song.