Sarcraft II HotS Cinematic with dubbed voices?

[Darktoothone]

I'm not exactly sure if this is the right place to post this or not, but I stumbled upon this video and got to wondering what program(s) the people would have used to change their voices they way they did.

Are there any free programs that can do this?

https://www.youtube.com/watch?v=G5VEKCpOTbs

[Oogly]

Tickled me good that.