After blinking 20 km away, Karsha stopped using the blink skill and decided to walk back to the sect. He could have flown, which would have taken him less than 10 seconds to get there, but he didn't want to start revealing all his trump cards. He even refrained from using the Blood Manipulation skill, but that doesn't mean he didn't benefit from the ball-kicking attacks.
He took a sample of their blood and discreetly stored it in his space ring without anyone noticing. Thanks to his powerful kicks, the victims bit their lips in pain, allowing him to stealthily retrieve a drop of blood from Vance and store it in his space ring.
The last ability of the Blood Manipulation skill seems to be more than just a tracking skill. Although his mastery of the skill isn't great now, when he reached B mastery during his battles on the island, he sensed there was more to the skill than he initially thought.