Half-Life 2: Off Limits Tactical Video

This is still a work-in-progress, but gives you an idea of the final result. As a human player, you won't be entirely defenseless. You can use the alien vision to your advantage, as you can actually blend in with the shadows, you become more invisible the darker the spot you're in. In dark spots only an experienced alien player will spot you. Don't fire a single shot though, as you'll light up like a torch to the alien.

As said it's still work-in-progress, you can still see the shadows and weapon models, but when it's finalized the alien experience will be complete.