In the most recent arcs we’ve learned about the advanced forms for the different types of Haki, namely Advanced Observation Haki (Future Sight) and Advanced Armament Haki (Emission).
However, so far we’ve not been introduced to an advanced version of the third type of Haki, Conqueror’s Haki.
So far, its most notorious usage has been for knocking out weak characters and taming wild creatures. Though still useful in the right circumstances, it’s safe to say the practical application of this type of Haki must go beyond what we’ve seen so far in the story, or it wouldn’t be such a terrifying power, as it’s been mentioned multiple times.
What this theory proposes, is that there’s one potential use of Advanced Conqueror’s Haki we’ve already seen in the story, and that is the power to summon, and even control, storms. The range of this ability can go from summoning storms (depicted as the clouds turning black), controling the wind, the waves, and even lighting. The idea behind Conqueror’s Haki seems to be about establishing dominance. So far, that dominance has been over other people and wild creatures. That’s why an evolved version of this ability would have to take it one step further, establashing dominance not only over others, but over nature itself. That’s why this would be Advanced Conqueror’s Haki.
We’ve seen situations in which effects of this nature have been present in the story without explanation, and though some might claim they’re just added for dramatic effect, it’s worth going over all of them, as many of them involve characters with confirmed Conqueror’s Haki:
In Chapter 100, Dragon saves Luffy from Smoker by summoning a gust of wind. Although as of this moment, we don’t have confirmation of Dragon’s powers, it’s a safe bet that he has Conqueror’s Haki, and probably a very strong one. Also, assuming he was the one that saved Luffy from Buggy the previous chapter by summoning thunder, and what Smoker says a bit later about how the wind is blowing in a direction that’s helping the Going Merry escape, we can assume he has a control over the storm, and it isn’t just a natural fenomena that follows him around.
There’s more evidence of this in Chapter 586, when Dragon meets Sabo. We also see there’s a storm in this scene. Later, when the Revolutionaries help the people of the Grey Terminal escape from the fire, the wind creates a path by putting out some of the flames. It’s still possible that Dragon’s power might be connected to some sort of Devil Fruit rather than Haki, but we’ve also seen some similar effects around other characters.
Another character who’s often followed around by storms is Roger. In Chapter 0, when Roger and Shiki face off against each other it’s in the middle of a storm, and the sea is raging. Though we don’t see the fight, we know that the storm sunk half of Shiki’s fleet, yet it seems like Roger’s crew was unharmed. Furthermore, in Roger’s execution, as soon as he was killed it started to rain. Though this might be unrelated to this theory, it could also be explained as Roger stopping the rain with his Haki, and then as soon as he passed away, that pressure was released and the rain started to fall.
In Chapter 434 we see Shanks pay a visit to Whitebeard. As he walks toward him activating his Conqueror’s Haki, parts of the Moby Dick crack out of the pressure of his power. In this case, Shanks was just trying to appear slightly intimidating. In a more serious situation, it’s not crazy to assume he could use this same Haki to affect something bigger, like the air pressure, therefore creating storms.
Later in the same chapter, when Shanks and Whitebeard (two characters with confirmed Conqueror’s Haki) clash, the sky splits in two. This could very well be a side effect of this technique of Conqueror’s Haki when it’s used. This is the first time we see this happen in the story, but not the last.
In Chapter 951 we see another clash between two Emperors, Kaido and Big Mom. The effects are similar to the one seen previously, with the sky splitting, and the sea raging around Onigashima.
In the most recent clash in Chapter 966 between Roger and Whitebeard, we see a great gust of wind that pushes back the clouds, and then a storm in the island during their 4 days fight.
I believe that’s all of the evidence there is regarding this potential type of Advanced Conqueror’s Haki. If this type of ability actually exists, out of the 14 characters that currently confirmed to have Conqueror’s Haki, there would be 5 confirmed to have it: Roger, Whitebeard, Kaido, Big Mom and Shanks (and Dragon, assuming he’s a Haki user). That would make it even more rare than regular Conqueror’s Haki.
In summary, an Advanced form of Conqueror’s Haki is creating storms that can be controlled by the user to summon wind, lighting, and dominate the sea.
*Theory by RoderickThe13