Karyk had entered the ship of a young man who was powerful enough to affect the river of time with his battle.
More than his own strength, it was due to the strength of his Bloodline, which was no weaker than the Bloodline of the Angels.
Karyk had already observed that the Time Lord had been quite considerate towards the young man, despite his actions of affecting the flow of time.
It was less like a lord talking to a subordinate and more like someone talking to their nephew. That became one of the reasons Karyk chose to board the man's ship.
He had also heard that the man's father had a conflict with the Angels, which gave Karyk a lot more confidence about using this opportunity to further his understanding of the world.