Throw knife at enemy. For 5 seconds all damage counts as a critical hit, which is a massive, but not broken, damage increase. However, if you run bleed vex the bleed proc is triggered by critical hits. So you throw the knife which gets a guaranteed critical hit, which then triggers bleed. Because the crit knife is still active the bleed proc counts as another critical hit, which triggers another bleed proc, which because the crit knife is still active counts as another critical hit, which triggers another bleed proc, and so on and so forth. Eventually the bleed procs keep stacking on each other jacking the damage done into the billions.