"its time I teach you something new" that has got me thinking a lot, was it just mixing the gears? no it couldn't of been, luffy knows how to mix gears already, but then again, could it be?
Could it be a forth form of haki, he did say it falls into 3 basic types, meaning their could be more complex stuff that falls into its own rarer category, its a shonen so I wouldn't put it past them (maybe)
What do you guys think? I really want to hear your opinions on this on what Relieh meant. could it of been hinting at a gear 5th that isnt AS taxing but more of an all round attacker. I look forward to reading your comments on this matter.