In Blacklight, simple mechanical gun-skill will not suffice, as it is only half the battle. While you are engaging hostiles, it is key that you are constantly moving. Being unpredictable leads you to take less damage, the less damage you take the more enemies you can engage. For health builds that fall in line with Viper J. Vansaint, you should always employ these tactics, in addition to jumping, and staying out of sight from enemies. For builds such as Grendel K. Moreau fast moving is still important, however damage can be tanked more easy.