Goon 1 has a mo-hawk in the first scenes, but in the later it has disappeared. The Zombiemaster emphasizes this by running his hand over the top of Goon 1's head in one scene.
When the zombie hunters are riding the cab the cameraman is reflected in Ivo's glasses.
In the scene when Ivo is carried after being wounded, you can see the actor's cue card mirrored in his glasses.