When Garran heard it, he was taken aback. He hadn't expected Fenix to be so powerful, especially since Butler Zen was known as the strongest Conqueror Rank in their entire family.
Not only that, Butler Zen was so formidable that even Lucan's protector would likely lose against him if they fought seriously. Garran knew this because Butler Zen himself had once estimated a 60–70% chance of defeating Lucan's protector.
That was precisely why Butler Zen accompanied Garran when they went to confront Lucan. Even if they ended up cornered by Lucan's protector and Draven's men, Butler Zen was confident he could at least help Garran escape even if it came at a price.
Furthermore, Garran himself was also stronger than Lucan and was regarded as one of the top fighters in the academy among those at his rank.