Any way to make a vocoder blue effect?

I want to make a mod for half-life but all the scientist voice lines sound like this https://www.youtube.com/watch?v=Oe_Vt7yzyU4 problem is, I don’t have Sony Vegas.

Audacity has a vocoder , but for intelligible speech the free MDA Talkbox plugin is better …
http://mda.smartelectronix.com/

Alright, I wanna try and create an effect like this https://www.youtube.com/watch?v=EfmtyMHFnvc

MDA Talkbox plugin can produce something like that …

Audacity does not have any instruments: you’ll need other software to play the tune.