True to his design as an assassin droid, HK-47 was a dangerous opponent, able to fight effectively in a stealth operation as well as in open combat. His combat programming made him a deadly combatant with a large variety of weapons, including blasters of any design as well as a multitude of droid weapons such as flamethrowers and carbonite projectors. HK-47 had a particular affinity for blaster rifles, using the Droid Assassin's rifle primarily, often citing the satisfaction he derived from using them in many combat scenarios. As a Jedi hunter, the droid was knowledgeable in many techniques for assassinating Jedi, which he explained to the Jedi Exile so she could better defend herself against her enemies. When faced with a Jedi, HK-47 utilized various weapons specifically selected to be most effective against lightsaber techniques, such as grenades, sonic screamers, cluster rockets, plasma charges, poison gas and mines, showing the droid's versatility in combat. These weapons could not be deflected by a lightsaber, and sonic weapons were useful in shattering a Jedi's concentration, preventing the use of Force powers. Mines and gas were useful in catching a Jedi by surprise, giving HK-47 the advantage in combat. HK-47 mentioned using a sniper rifle to attack from long range in order to avoid detection. In addition to these weapons, HK-47 also would attempt to erode the will of his opponents and make them doubt their beliefs, which he found to be an effective method for weakening their concentration and disrupting their connection to the Force. The droid also found attacking a Jedi's allies, as Jedi would often sacrifice themselves to save an ally.
In addition to his combat proficiency, HK-47 also possessed many other skills. Like many droids, HK-47 was a mechanic and had at least some knowledge in demolitions and slicing. During his journey with Revan, he could start a fighter simulation so that Revan could practice his skills at manning the turret of the Ebon Hawk. Revan also upgraded HK-47 on various occasions, increasing his overall efficiency. As much of his original programming was based on protocol subroutines, the droid was capable of acting as a translator, voice impersonator, and as a protocol droid in many other respects. He was fluent in Galactic Basic Standard, Tusken, Binary, Jawa Trade Language, and boasted that he was fluent in over 6,000 forms of communication.
Several modifications were made to HK-47 throughout his life span by his many owners, modifications that served to re-enforce his abilities and enhance his performance. Most of these modifications were damaged beyond anything less than intrusive repair after his dismemberment during his second service to Revan.
