Blood: One Unit Whole Blood is the perfect diamond among the perfect pearls on GOG.com. Whoever plays and enjoys FPS nowadays, will certainly remember Blood from their old days of gaming. Even better than Duke 3D and Shadow Warrior, Blood throws the player into a nightmarish atmosphere, full of demons and crazy cultists. Of course, as the name suggests, there is a lot of BLOOD and gore in the game. The game is built upon the world-famous Build engine, by Ken Silverman, and it's the best Build game ever (it uses some engine resources that other games don't, making it much more sophisticated than Duke and Shadow Warrior, other two great Build engine games). Also, by releasing Blood, GOG.com solved a long-term issue the Blood community had: Windows XP compatibility. JUST BUY IT, it's a must have.