Sylas stopped a long distance away, huffing for breath.
Using his fusion ability took a lot out of him. Although he felt that he could activate it again, if he did so, it was likely that the hit to his stamina wouldn't be as simple as just gasping for breath. His heart might even directly explode.
He felt those feelings even more now that he could take on 80% of the Basilisk King's stats.
That told him one very important thing.
His Legendary Profession was well beyond his abilities to fully control, and it quickly increasing in Levels might be more of a detriment to him than anything else. He would have to seriously think about slowing down if he could.
All things considered, the Basilisk King was far weaker than the current Sylas back then, let alone now. Yet, fusing with it put so much pressure on him, and it seemed to have increased exponentially with the length of time he remained fused with it for.