Play Half-Life with friends! Players fight computer-controlled monsters through the original Half-Life storyline or hundreds of available co-operative scenarios. Also includes a plethora of new weapons, enemies, visuals and gameplay systems. Customization features allow each map to use its own unique weapons and enemies.
This is the sven coop opposing force ud pack by r1chard found on the trusty crowbar facebook page and its an alpha patch, enjoy :D
It looks pretty cool, or rather, these models were used by an analogue of Black Mesa, namely this is a remake of Half-Life 1 on the engine, we all already know, but the models of HECU soldiers were borrowed from Call of Duty: Modern Warfare 2 2009 and then they changed the textures of the models and here even slightly changed parts of the models but it looks cool.
And here I am making Sven Co-op: Redux