The Falcon Jewel is an orange jewel, worn on a necklace connected to a silver bird head shaped topper, that acts as the focal point of the Mountain Fortress Adventure within the video game version of "JUMANJI", replacing the Jaguar's Eye of the Jaguar Shrine Adventure. The Jewel's magic provides fertility to the land of "JUMANJI", so long as it stays in the sun.
The dastardly Jumanjian conqueror, Jurgen the Brutal and his army returned to "JUMANJI" and invaded the Avian Province, home of the sacred Falcon Jewel, which is worn around the neck of the village elder, and has been guarded by the people of the Avian Province for hundreds of years. Jurgen attacked and stole it from them in order to sell it to a crime syndicate led by the Brothers Kebabic, so both groups can combine forces. As a side effect, stealing the jewel caused a drought to strike the land, similar to the Jaguar Shine Adventure; when Professor Russell Van Pelt stole the Jaguar's Eye and cursed the land. This chain of events forced Nigel Billingsley sending a letter to Dr. Bravestone and his allies to return and retrieve it.
When the Brantford people Martha and Fridge returned to "JUMANJI" to find Spencer, along with Spencer's grandfather Eddie and his friend Milo, Nigel was there to greet them again, and proceeded to fly the quartet while briefing them on their adventure objective, telling them in a cutscene, he told that he had again sent a letter to Dr. Smolder Bravestone and his companions to come and help them stop the conqueror Jurgen the Brutal, who had stolen the sacred Falcon Jewel, he then gave them a map and dropped them out of the plane at "The Dunes" level as part of his programming.
The group first meets Jurgen at the Oasis, where Spencer, in the avatar of Ming Fleetfoot, tries to steal the key to the chest with the Jewel, but is stopped by Eddie, in the body of Bravestone, causing Jurgen’s goons to catch him. Jurgen retrieves the key and then kills him with an axe, he and his men then pack up and leave.
Jurgen is next seen at his ice fortress on top of Mt. Zhatmire. Fridge and Bethany, who had switched back to the avatars of Franklin "Mouse" Finbar and Shelly Oberon, pretend to be the Brothers Kebabic, in order to get inside the fortress. When Jurgen sees them, he asks them about their sister, who is due to marry him in exchange for the Jewel. Martha shows up and pretends to be her, but one of Jurgen’s men informs them that the Brothers Kebabic are still on their way to meet him, outing Fridge and Bethany as imposters. The others arrive and Spencer, now back in Bravestone’s avatar, fights him, but is no match for Jurgen’s strength. Spencer pulls out the "JUMANJI" Berry, causing Jurgen to leave and have his men finish them off.
Jurgen attempts to make his getaway to meet the brothers on his zeppelin with the jewel, but Spencer goes after him and fights him inside the zeppelin. Spencer uses the "JUMANJI" Berry to weaken Jurgen, just as the zeppelin is shot and starts to come down. Spencer then tackles Jurgen out of the zeppelin and grabs the Falcon Jewel while grabbing hold of a nearby rope, sending the warlord plummeting to his death.
Once Bravestone (Spencer) handed them the necklace, Ming (Eddie) and Cyclone (Milo) were able to fly into the sunrise skies above, fill the Jewel with energy from the sun rays, and all the players could save the game by calling out the name; "JUMANJI". After the now seven avatars succeeded in retrieving the Jewel, Nigel arrived on a dog sled to shake their hands individually to congratulate them on their success and return them home safely for winning the game. Nigel takes possession of the jewel and promises to guard it with his life and return it to its rightful place.
- The Falcon Jewel has similarities with the Shankara Stone of Mayapore ("Indiana Jones and the Temple of Doom"):
- It was taken by evildoers;
- The companions are assigned to retrieve it;
- Its absence caused the water sources to dry up and the local agriculture failed.