[member="reddestror"], [member="Silara Vantai"], [member="Maleus"]
Among one of the passengers there was a robed figure sitting in the back, his face and indeed the whole body covered in bandages, old tattered robes of a traditional Jedi hanged loosely off of his body, his shape and identity unknown under the thick layer of linens and wraps that covered him, the eyes hidden behind black tinted goggles.
It was HK's usual appearance when trying to blend into the hordes of organics, it was that of a leper, neither his sight nor smell was too appealing, the bandages were caked in dried blood and dirt alike, he just had that air of a diseased being around himself.
As the mad man begun to cut organics down the robed figure would stand up, his shape was that of a human, since the droid did not look like an actual HK droid anymore, not even underneath the bandages, his current body has long since been upgraded to have a more humanoid silhouette in order for the machine to wear additional armor, or robes as he did now.
Either way, as the Mad Man kept on slashing or just waving his lightsaber around, the masked droid raised his hand to him, coming face to face with the villain, his hand would be in that of an open palm, his feet shoulder-width apart, dominant foot in front. More or less it just seemed like he was motioning for Serge to stop, through the thick cloud of smoke the man would probably run into the hand face-first, this would only be confirmed by the muffled words of the being,
"Cease."
Calm and collected as always, it wouldn't be the first time he would have to fight a lightsaber wielding foe.
As much as it seemed that he was just motioning for Serge to stop, those more versed in martial arts who were close enough to see through the smoke, droid had no problem doing that with his photoreceptors, would see past the charade to what droid's stance really was.
Echani open-palm battle stance.
As to the question on what was HK doing there, he always had close ties to Dantooine, during the Old Republic the droid served the Jedi Enclave on the planet as a training droid, it was here he was taught the ways of the Jedi and arts of the lightsaber.