Castiel and Frank Reagan could also be an interesting pairing. Castiel with his angelic powers and Frank with his leadership and experience in the police force. Castiel might not understand all of the human politics and procedures that Frank deals with, and Frank might be initially shocked by Castiel's otherworldly nature, but they could find common ground in protecting the city from a major supernatural disaster.
Castiel and Paige Matthews could also make for a great pairing. Castiel's otherworldly, angelic nature and Paige's half - witch, half - white - lighter abilities would lead to some unique interactions. They might struggle to understand each other at first, but as they learn more about their respective powers and purposes, they could form a strong alliance to combat a powerful enemy that neither of their worlds could handle alone.
Definitely Dean Winchester and Oliver Queen. Dean's rough - and - tumble, no - nonsense attitude combined with Oliver's brooding and strategic mind would make for some great banter and action scenes. They could bond over their experiences of losing loved ones and their determination to protect the innocent.
Definitely Barry and Dean. Barry's positive attitude and scientific mind would contrast well with Dean's tough - guy, no - nonsense hunting style. Another interesting pairing could be Iris and Sam. Iris is a strong - willed journalist, and Sam is the more intellectual and empathetic Winchester. And then there's Cisco and Castiel. Cisco's love for creating new tech and Castiel's otherworldly nature would make for some really fun interactions.
Definitely Tony Stark and Dean Winchester. Tony with his high - tech gadgets and smart - aleck attitude, and Dean with his love for classic cars and no - nonsense approach. They would have some really interesting banter, and Tony could probably learn a thing or two about survival from Dean, while Dean might be impressed with Tony's technology.
Definitely Piper and Dean. Piper's power to freeze time could be really useful when Dean is in a tight spot during a hunt. And Dean's no - nonsense attitude could balance out Piper's more emotional side.
Definitely Clark Kent and Dean Winchester. Clark with his superpowers and strong moral code, and Dean with his tough - as - nails hunting skills and loyalty. They could have some great banter as they come from such different worlds but find common ground in protecting people. Another interesting pairing could be Sam Winchester and Chloe Sullivan. Sam's intelligence and knowledge of the supernatural could pair well with Chloe's investigative skills.
Oliver Queen and Dean Winchester would be an interesting pairing. Oliver is a brooding, justice - seeking vigilante, and Dean is a tough, monster - hunting badass. They both have a sense of loyalty to their causes and a no - nonsense attitude. They could bond over their shared experiences of losing loved ones and their determination to protect the innocent.
I think Shirou Emiya from Fate and Rin Okumura from Blue Exorcist would be an interesting pairing. Shirou is a self - taught mage who is very determined, and Rin is a powerful exorcist. They could learn a lot from each other's fighting styles and magical abilities.
Ciel and Dean Winchester would be an interesting pairing. Ciel is a young, determined noble who is used to getting his way, while Dean is a tough hunter with a lot of experience. They could learn from each other's ways of dealing with difficult situations. Ciel could teach Dean some of his strategic thinking, and Dean could show Ciel how to handle more physical threats.
Michonne and Sam Winchester would be a great pairing too. Michonne is a skilled fighter with her katana, and Sam is very intelligent and well - read. They could work together to research any possible links between the walkers and the supernatural. Sam could also help Michonne come to terms with any new, otherworldly threats they encounter.