Jaune, Nora, Pyrrha, and Ren fighting the Beowolf. Jaune, massively outclassed by the beast, still manages to escape its grip by using his Blacksmith skills to burn it while Nora, Pyrrha, and Ren are able to immediately unite together and fight the Grimm as a coordinated unit. When even their continued assault fails to put it down, they lure it into a house and destroy the support beams, pinning the roof on top of the Beowolf and allowing Jaune to finish it off, gaining two levels in the process.
After Pyrrha spends most of the guild's budget on transportation to Mistral and the rest of the group are wondering whether or not they'll have to camp outside of town and forage for their dinner, Jaune, who comes from a family of Shopkeepers and is aware of how much Adam Smith Hates Your Guts, is able to assuage, flatter, and blackmail his way into getting the whole guild food, drink, and lodging for the night with a mere 500 Lien. The rest of the guild are absolutely astounded.
When the rest of the crew on the ship to Mistral are put to sleep by a spell, Jaune manages to power through it, wake everyone else, and then join in fighting off the invading Deserters after having already taken an arrow to his side. Special mention goes to his fight with the Berserker captain. He is already injured and in a Blade Lock with an opponent that outclasses him in terms of both Levels and experience. He then thinks of the irony of being killed by a weapon forged by a Blacksmith and has a realization. He uses his position to super heat and then rapidly cool the haft of the enemy's axe, weakening it enough for him to carve through both it and his opponent in a single swing.
Jaune's insistence on the guild and their charges staying to help the faunus village that had been buried by an avalanche which then prompts Ruby to step up as well and direct the rest of the guild on how they too can help the trapped and injured villagers.
The Hunters' fight against Glenn Vuori. The Lancer completely thrashes almost the entire guild with only Ruby, Blake,Pyrrha,and Jaune able to continue fighting her. Even so, they manage to injure her to the extent that she takes Jaune as a hostage with her weapon already pierced through his armor and right above his heart. Then, when she tries to finish him off, she sees that her spear tip had been melted into Jaune's armor, both rendering it useless and giving Ruby all the opportunity she needs to reap.
Merlot is almost impervious to any form of damage that isn't fire-based, leaving Kaedin, Weiss, and Yang as the only ones able to deal any significant damage to it. Jaune realizes that even their strikes aren't doing enough harm and that they're fighting a losing battle, so he has the others lure it right next to the temple roof where he then pushes building's supply of kindling and sacrificial lumber onto the Grimm before having Weiss set it alight for massive damage.
Within moments of hearing about the horde of Grimm coming to attack Magnis, and subsequently Vale, Jaune convinces General Corvo to use the Mistrali army to defend the city by revealing that Cinder is in Vale, and would be killed by the Grimm if he did not defend the keep.
He then goes on to convince the Commander of Magnis to ally with the Mistralians to fight off the Grimm. The Greycloak Scribe that harried them earlier on their quest then attempts to enact a coup that would see the Mistral army barred from Magnis and the whole city destroyed. Jaune briefly considers forcefully stopping him and his entourage but stops once he remembers his past failures in that regard. He then has one of the opposing soldiers come forward and read aloud the message on Cinder's Scroll. Once the opposing Nobles and Soldiers realize the magnitude of the missive Jaune presented, he shows them the other casing that bears the seal of Vale. He and Weiss then bluff them into believing that they were given special authority by the king to investigate the commander of Magnis and that they have the authority to incarcerate any individual they see fit. The Scribe is forced to back down and the Mistrali army is peacefully allowed into the city.
In Chapter 15, Jaune fights a Greycloak Mage who specializes in making portals. First, Jaune plays on the Mage's hubris to find out where he sent Torchwick and Neo. Then he charges. Naturally, the Mage teleports whenever Jaune gets near him. He is able to outsmart the Mage by realizing that his opponent always teleports to wherever Jaune was last and makes sure that a pillar that was already unstable would fall on his previous location. When the Mage tries to step through a portal to evade said pillar, his foot gets stuck in the temple's gold flooring which Jaune had etched a crack into. He only has enough time to wonder "How?" before he is crushed.
Jaune gets a small one in chapter 8 when he stabs Salem in the back for psychologically torturing Blake.
Watts gets one in chapter 8 for managing to resurrect Willow Schnee as his slave, and do it without getting backstabbed by Salem.
After gaining four Levels for killing Willow and Watts, Jaune learns a new skill, Purify Object, that both hurts Salem and forces her to retreat, and this is after already managing to wound her twice. He also realises that his Path isn't just helping him fight Grimm; it's helping him fight Salem.
What is perhaps Jaune's most awesome moment yet comes at the end of chapter 12 wherein, after he reaches the realization that he's finally content to be himself, Class and all, Jaune and Ansel's Captain of the guard meet with an entourage of Mistralian soldiers who are ostensibly there to ask for directions and resupply. When one of them, a Knight, attacks the captain while their backs are turned, Jaune saves the guard's life and effortlessly disarms the soldier. When the Mistrali commander reveals that not only do they intend to kill the villagers and burn down the town, but that the Peace Conference itself is a trap, Jaune burns the Knight alive and from his armor forges Crocea Mors anew before giving them one hell of a speech.
"It was a mistake," I said, softly, but with a voice that carried, "To believe that a Blacksmith is ever without a weapon. It was a mistake to believe that a mere NPC is no danger. It was a mistake to come here prepared for war. And it was a mistake to try and betray us. But most of all, it was a mistake to break the Grand Treaty."
When Cinder summons a wall of flame to prevent the Valean forces from stopping her and her king, Jaune forges himself a suit of molten armor and passes through entirely unscathed. To say that Cinder was surprised would be putting it mildly.
The ending certainly qualifies. As Jaune lays dying after having nearly bested Cinder, he grabs the sword she impaled him with and begins to forge, using both it and himself as the material. The results are so unbelievable that the point of view actually changes for the very first time in the entire story and Cinder has to doubt the impossibility before her eyes.
"Impossible," Cinder whispered. JAUNE SWORDMASTER
Chapter 15 reveals that Jaune is now a multi-classed character, able to switch between being a Blacksmith and Swordmaster at will.
While accidentally implying that the King of Vale is a bandit definitely qualifies as a Mass "Oh, Crap!" moment, the fact that the leader of Vale personally made the trip to Ansel really emphasizes just how seriously Jaune and his hybrid status are being treated, as well as the high regard the King holds him in. It also hints at just how much of an impact Jaune and the Hunters Guild have had on Ansel. What was once an unremarkable village is now a rapidly expanding population center, has no Noble Caste oversight, armed the Labor Caste, hired ex-Mistralian mercenaries, changed their flag, and owes Undying Loyalty to a man who has seemingly defied the basic laws of their universe.
As flat-out horrifying as the revelation is, Raven, leader of the Greycloaks, is Level 112. For context, most Heroes max out at 70, the best reach 80, and legends are spoken of heroes who reached Level 90.
After five days of captivity and torture, Jaune is eventually persuaded to forge Raven a sword in exchange for freedom for himself and Lisa. The blade, whose forging alone earned Jaune four Levels, is composed of Starmetal and engraved with an eldritch rune that reads "Seal/Contain". Raven declares it to be a perfect weapon which may be capable of killing even Salem herself.