C15 Unlimited Military Power

Without a doubt, Luffy and the others were no match for Shiki before the main character's halo was fully activated.

After all, the latter was able to exchange blows with Karp and Warring States twenty years ago. Even if he was defeated and captured, he had also torn down half of the navy headquarters' experts.

Perhaps the grass-hat group two years later would be able to fight Shiki head on