Patch 4.0.6 (8-Feb-2011): Kill Command’s damage has been increased by 20%.
/Patch 3.0.2 (14-Oct-2008): This ability now increases the damage done by your pet’s special abilities by 60%. Each attack will reduce the damage bonus by 20%. 1 minute cooldown.
Patch 2.1.0 (22-May-2007): Kill Command has been removed from the global cooldown. The shout animation has been removed.; This ability will now still work even when your pet is out of your line of sight.