Imagine you're a Pyro.
"Build a Teleporter here!", you yell at the nearest Engineer, but he doesn't get what you want to say and uses his metal to build a dumb Dispenser.
"Watch out, Sentry ahead!", you try to warn a friendly Scout but all he hears is "Mmmph", so he gets torn to pieces by a turret.
Don't you hate that?
Wouldn't it be a gain for everyone if you could communicate with your team a bit better?
Well, here comes the answer to your calls:
The WingnutLevel 1-99 BirdEffect: 66% more understandable voice commands.
"As a nestling, the tale of the legendary Phoenix inspired this Parrot's undying wish to surround itself with flames. When an 'accident' including a can of highly leaded paint and an extraordinarily bored pet-shop owner permanetntly rendered him completely fireproof but also flightless he decided it was time to quit his job in the cage-sitting industry and enlist for a position closer to the fire."(Paintable.)
So, it's a Parrot.
Sitting on the Pyro's shoulder.
Doing the voice commands for him.