Perhaps there is a prophecy in the Naruto world about a great danger that can only be averted by finding a certain item in a tomb. Naruto, not knowing much about tombs, gets transported to Lara's world. Lara, being an expert tomb raider, decides to help him. As they progress through the tomb, they discover that the item has the power to either save or destroy both their worlds, and they must make a difficult choice at the end.
Well, one possibility could be that Naruto, with his ninja skills, teams up with Lara Croft in a tomb raiding adventure. Maybe they are searching for a powerful artifact that has ties to both their worlds. Naruto could use his shadow clones to help in exploring different areas of the tomb at the same time, while Lara uses her knowledge of ancient languages and traps.
Well, perhaps in the fanfiction, Lara Croft is exploring an uncharted planet when she stumbles upon a Halo ring. This attracts the attention of the Covenant, and Master Chief arrives to deal with the situation. At first, there's some tension between them as they come from different worlds and ways of doing things. But as they start to understand each other's motives and skills, they combine Lara's knowledge of ancient mysteries and Master Chief's combat expertise to fight the Covenant and figure out the secrets of the Halo ring.
One idea could be that Lara Croft is exploring an ancient tomb and stumbles upon a hidden Umbrella Corporation facility. She discovers that they were experimenting with some sort of ancient virus that was sealed in the tomb long ago. The T - virus has escaped and is starting to mutate the local wildlife and some of the tomb's guardians. Lara has to team up with a Resident Evil character, like Jill Valentine, to stop the virus from spreading further and also figure out how to deal with the newly awakened threats in the tomb.
One possible plot could be Lara Croft discovers a Prothean artifact during one of her adventures. This artifact has a connection to the Mass Effect universe, perhaps it contains data about the Reapers. She teams up with Commander Shepard to figure out how to use this information to stop the Reapers or some other threat that is starting to cross over from the Mass Effect universe into her world.
A possible plot could be that there is a powerful and mysterious force that is causing chaos in different parts of the world. Both Lara Croft and Wonder Woman are independently investigating it. Eventually, they meet and decide to team up. They travel to different locations, from ancient ruins to modern cities. During their journey, they exchange stories about their past adventures and develop a mutual respect. They then use their combined knowledge and powers to track down the source of the chaos, which turns out to be a mad scientist who wants to use the power of the gods for his own gain.
A Tomb Raider and Uncharted crossover fanfiction could be about Lara Croft and Nathan Drake teaming up. Maybe they start off as rivals, both after the same ancient artifact. But as they face various traps and enemies, they realize they need to work together. They could share their skills, with Lara's survival skills and Nathan's sense of adventure complementing each other.
A common plot point is the culture clash. Naruto, coming from a world of ninjas, and the Tomb Raider world which has its own archaeological and exploration - based culture. For example, Naruto might be baffled by the high - tech gadgets Lara Croft uses, while she could be intrigued by his chakra - based abilities.
The plot could involve the IT guy being hired by a shadowy organization that is actually exploring an ancient tomb. Unbeknownst to them, the IT guy discovers their true, nefarious intentions. He contacts Lara Croft for help and together they have to stop the organization from using the power or treasure within the tomb for evil purposes while also dealing with the tomb's various traps and puzzles.
Perhaps the IT guy is hired by a secret organization to assist Lara Croft. His role could be to maintain and manage the high - tech equipment she uses during her adventures. Along the way, they face various challenges and the IT guy has to use his wits and technical skills to keep them out of trouble. For example, when they encounter a booby - trapped tomb, he has to figure out how to disable the security systems.
At first, their interactions might be a bit rocky. Naruto is used to his own loud and energetic ninja world, while Lara is more of a lone wolf in her tomb - raiding adventures. However, as they face challenges together in the tombs, they would start to trust each other more. Naruto might crack jokes to lighten the mood in the tense and often dangerous tomb environments, and Lara would start to rely on Naruto's unique abilities, like his ability to sense danger with his chakra, which she doesn't have in her own set of skills.
Another plot could be set in a world where the myths and legends of both Uncharted and Tomb Raider exist simultaneously. Nathan and Lara are called upon by a secret society to retrieve an item that can save the world from a cataclysmic event. Along the way, they discover that their families' pasts are intertwined with the mystery of this item, leading to some emotional revelations as well as exciting adventures through jungles, tombs, and ancient ruins.