Ivankov on par with the likes of Katakuri, Jack, King, Queen and Marco?

[Warmmedown]

He never seemed phased by the battle danger at Marineford, besides worrying about Luffy's safety.

 

[Future Warrior]

He's relying mostly on portrayal unfortunately. Probably a strong Yonko Commander calibre above Jack, but not the rest.

 

[SSJ2]

Does he even have Haki?

 

[Future Warrior]

Sanji must've learned it from him.