Combine Soldier

The Combine Soldier is very similar to his final incarnation in behavior and in the equipment he uses.The most noticeable difference are his textures. The prototype Combine Soldier has yellow underarms instead of white, a lighter camouflage with a different pattern, a darker head, red eyes, and what appears to be the logo on the Strider and Combine Gunship pasted on his back. The Strider logo lacks transparency, making it look like he had a black box with the texture on it pasted on his back.

The prototype Combine Soldier not only lacks a lot of animations compared to the final version, several of his animations are different from the final's. Some examples include kicking the player instead of hitting the player with his gun, a clunky grenade toss animation that has the Combine Soldier tossing with his left arm instead of right, and a different running animation.

He also uses completely different sounds in the prototype. Like the prototype Civil Protection, the Combine Soldier uses full sentences instead of the "fragments strung into a sentence" system that the final Combine Soldier uses. He also lacks the lingo that the final Combine Soldiers use and does not talk to the Combine Overwatch voice. The voice modulation for his voice clips are completely different and makes it extremely difficult to understand what he's saying because of how garbled he sounds. Fortunately, there is a set of earlier voice clips that lack the extreme garbling, making it easier to understand (though not simple because of the low quality the original recordings are).

Of note is that the prototype Combine Soldier has animations for launching grenades from the old AR2, the XM29 OICW. This suggests that enemies were able to launch grenades from guns that have grenade launchers (specifically the OICW), but the ability was removed some point down the line.

Camo Soldier
The yellow lenses are seen again in a more recent version, a Camo Overwatch Soldier, which can be found as a model for the Camo Sniper in the playable Beta files, although all Overwatch Soldiers were to look that way at this point of the game's development.

Combine Armored Soldier
This was intended to be a variant of the Combine Soldier and it was intended to be very strong, after his death his armor disappear how when the player use the energy ball to a soldier.

It was intended to have some weapons how the SMG 2 and the Pulse Rifle.