It's a Screenshot from the Half Life 2 beta which you can still find to this day. The combine soldier was one of teh original models holding a standard overwatch rifle. The creature of and in it's self is the Hydra, a void 'being' who was cut from the release but can still be found in the beta. But as numerous people who have played it and the very original 'sapper' of the data put 'It was intresting in theory, however less of a threat in actual combat'. Sorry if that sounded... know it allish.