Probably just the mocap actor.

link

Yeah. I saw a few set scenes and he's just a huge dude in a suit. I'm curious about the voice actor. Hopefully it's someone good.

@rickbarry: Hopefully they get someone who's Russian.

Deadpool 2016 took 5 performers to Completed
A voice actor- Voice
A Stand-in CG guy (Mocap)- On set
A Face model
A VFX of Colossus- Digital Domain
Animators for final tweaks

i would have like to have seen Colossus in his human form even if for a moment. Wouldn't even have to see his face.
The scene where he is in the kitchen watching the news. They could have had the camera come from behind and all we saw was the back of a decently large man. Who was eating breakfast. And as he's watching the news realizing its Wade (Deadpool), slam his fist down, calling for Negasonic Teenage Warhead (NTW) and transform and walk off angrily

Deadpool Colossus 5 performers

Deadpool 2 2018 took 2 performers this time
Same voice actor- Stefan Kapicic
Stand-in Mocap on set- Andre Tricoteux