Well since people have been talking about it since it’s been basically said Jaune will get his semblance this Volume, likely in the 11th Hour to tip the scales in our heroes favor, I thought I’d weigh in. This theory had been several separate guesses until combined into this which all made sense with the Forever Fall hint and the personality idea’s from last week. I’ll go into the personality traits that I feel explain this before saying my actual guess.
When Jaune first came to Beacon to fulfill his dream of being a huntsman he realized how “normal” compared to all the other students. The others all had cool weapons that could transform and become guns and all he had was an old sword and shield. Everyone else had these amazing super powers he had no such ability. He didnt even have the basic tool all hunters need to fight. Jaune was not Unique compared to everyone else. However....
It’s been shown that Jaune wants to better himself, Pyrrha had even said so in the video she made for Jaune from volume 4.
Those things said I feel those are the things that show toward his semblance. My theory for his semblance is that it will take aspects of his aura (strength, Defensive Shield, and healing factor) and turn them up to 11. Aura is not unique all hunters have it thus his feelings of not being special or unique. But at the same time it relates to the part of him the is constantly striving to better himself.
In Forever Fall pt 2 when Cardin goes to punch Jaune there is the flash of Jaune’s white aura and then when it dies down Cardin’s hand is hurt but also Jaune’s scared face and black eye are healed (something I feel people overlook when describing the scene for evidence of the semblance). When Jaune looks at his hands just after his hands faintly glow as his body did when his aura was first unlocked. Cardin’s hand hurt because he struck Jaune’s, at the time, extremely strong defensive barrier. While healing is part of aura it should have taken longer for those injuries to heal but they healed all at once instantaneously. This also plays into him having large amounts of aura to manage such an ability.
In my opinion the ability would be something he turns on and off like going super saiyan, depicted by his body having the white glow rather than being always on like Qrow’s misfortune. Like Super Saiyan the limiting factor will be stamina which Jaune has a decent amount and will be a large aspect of his training regiment going forward.
This may not seem like like a cool power in concept being better at the basic stuff that everyone else has but when you think about it it is very good especially for Jaune. The other character’s have had their semblances for a long time so they have already incorporated their power into their fighting style. With this Jaune wont have to change anything about how he fights as it’s just a boost to his normal self. Additionally it also plays into his fighting style/ role in the larger RWBY JNR Oscar Sun hybrid squad going forward, Jaune is the tank the defense and one of the few people who use mainly brute strength in their fighting style, along with Yang and Nora. The increase defense will allow him to take more hits for himself and the others and the healing can take care of the injuries from the attacks that get through.
It also fits into another personality trait his desire to protect. He and Ruby wanted to be heroes who protect people early on. His style of fighting is Sword and Shield, and also great sword but we saw him using it to deafened Ren and Nora from the Nuckelavee’s charge. Then Jaune had to put himself in situations where he tried to protect someone in someway from something, the blackmail with Cardin, Weiss’s smile at the dance with Neptune (this is more being chivalrous than outright protection but you get the gist since both are Knightly). He quickly responded to Ruby SOS which allowed JNPR to respond to breach quickly. His failure to protect Pyrrha weigh’s on him heavily and is a driving force for him to get stronger. My belief of him activating it will be him going to defend Ruby Weiss or maybe Oscar (or a combination) allowing him to take the deadly attack with ease.