This mod adds Cortana, voiced by Jen Taylor, from the Halo series.

With carefully spliced voice lines from her lines from Halo 3 and her Halo: Reach Firefight voice lines, Cortana will call out nearby enemies, point out objective locations, warn you to take cover when you are hurt, and more.

Fake preview:

Actual mod content:
https://www.youtube.com/watch?v=ppDUa9O7Eek

(Didn't have time to make more than one preview, but there's much more than just the one voice line in the game)