Conditions for Haki Awakening
“The power sleeping within every person in the world… but most people die without ever realizing it, or are unable to draw it out no matter how hard they try… ‘Not doubting’ — that is strength.”
This is Rayleigh’s line when Luffy begins his two-year training.
Sudden Awakening
During the Marineford War, Coby’s Observation Haki suddenly awakened.
A Navy doctor noted that Haki is normally drawn out through long training, but Coby awakened his through the shock of battle.
Usopp’s case: during the Dressrosa arc, when Sugar targeted Luffy, his Observation Haki suddenly awakened.
What Coby and Usopp had in common: both were pushed to their limits under intense stress.
Hypothesis: being driven into a corner and experiencing extreme stress triggers Observation Haki awakening.
Observation Haki is probably the easiest type to awaken; Armament Haki requires dedicated training.
Anger
So how does Conqueror’s Haki awaken? The answer is anger.
During blindfolded training, Luffy recklessly knocked over Rayleigh’s meal. Rayleigh got furious. This moment was depicted humorously as “anger is also Haki” — but I believe this is exactly the condition for Conqueror’s Haki awakening.
[Egghead Arc Precedent]
Zoro was struggling against Lucci when Sanji called him “dead weight.” Zoro exploded in rage — and Conqueror’s Haki manifested.
Zoro didn’t realize he had Conqueror’s Haki until Gavan told him. At Egghead, he happened to get furious at Sanji’s words, and that anger triggered his Conqueror’s Haki — allowing him to defeat Lucci.
There’s another crewmate whose Conqueror’s Haki awakened through anger.
That’s Nami.
After departing from Wano, Nami beat Luffy — and a Conqueror’s Haki effect appeared around her.
So the condition for Conqueror’s Haki manifestation is anger. For Sanji to awaken his, he probably needs to get as furious as he was when he discovered Absalom had been peeping on Nami’s bath.
Conqueror’s Haki Is Contagious
When Luffy uses Conqueror’s Haki, the word “shishitsu” (innate quality) is used. But when asked whether Sanji has Conqueror’s Haki, Gavan answered that he should have the “soshitsu” (latent potential).
The difference between these two words:
Shishitsu = the quality was there from birth and has already awakened. Soshitsu = the potential is there, but not yet awakened.
Luffy had Conqueror’s Haki innately and it awakened around the Tobio Riders arc — hence shishitsu. Sanji hasn’t awakened his yet — hence soshitsu.
But why could Gavan say Sanji has the potential? That answer reveals the secret of how Gavan and Rayleigh themselves came to have Conqueror’s Haki.
I believe Conqueror’s Haki is contagious. Gavan and Rayleigh both caught Conqueror’s Haki from Roger’s — and because Luffy’s Conqueror’s Haki has been spreading to Sanji, Gavan recognized that Sanji has the potential.
Oden’s Conqueror’s Haki Spread to Zoro
Zoro’s Conqueror’s Haki, however, I believe came from Oden.
In the colored version of the comics depicting Oden’s retainers’ final charge, effects resembling Conqueror’s Haki are visible.
Furthermore, Kaido — who should not be hurt by ordinary attacks — said: “Why does it hurt!? Why does the blade pierce!? Did they also inherit Oden’s flowing Haki?” — as if Oden’s Conqueror’s Haki had been passed down.
When fighting Zoro, who wields Oden’s sword, Kaido also sensed: “Why does Oden’s presence ride on that sword?” — perceiving Oden’s Haki in Zoro.
When Zoro first used Enma, the sword absorbed his Haki. When he reclaimed it, Oden’s Conqueror’s Haki entered Zoro’s body.
That is why Zoro awakened Conqueror’s Haki one step ahead of Sanji.