Gildarts and a powerful, ancient spirit animal. Gildarts is one of the strongest mages in Fairy Tail. If he were to partner with a very powerful and perhaps wise old spirit animal, it would be a very dynamic duo. They could face the most difficult challenges together and their combined strength and knowledge would be a great asset in the story.
Meilin from Spirit Animals and Gray from Fairy Tail could be paired. Meilin is a disciplined fighter with her own spirit animal. Gray is an ice - making wizard. Their personalities are quite different, with Meilin being more reserved and Gray having a bit of a cool - headed yet sometimes comical personality. They could learn a lot from each other, especially in combat where Meilin's strategic thinking and Gray's ice magic could complement each other.
A pairing between Sakura and Erza would be great. Erza is a strong and disciplined warrior in Fairy Tail, and Sakura has her own strength and tenacity. They could train together and learn from each other's combat styles. Maybe they would compete in friendly sparring matches, which would not only improve their skills but also strengthen their friendship in the process.
Goku and Natsu would be an interesting pairing. Goku's pure - heartedness and love for fighting would mesh well with Natsu's fiery and passionate nature. They could have some epic battles together just for fun, and then team up to take on stronger foes. Another good pairing could be Vegeta and Gray. Vegeta's prideful and somewhat cold demeanor would contrast with Gray's cool - headedness. They could learn from each other's fighting styles, with Vegeta showing Gray some of his Saiyan techniques and Gray teaching Vegeta about his ice - make magic.
Wanda Maximoff and Juvia would be a fascinating pairing. Wanda's powerful magic and Juvia's water - based magic could create some really unique and powerful combinations. Also, their different personalities - Wanda's more brooding and Juvia's more love - struck - would make for some interesting interactions.
Gray and Weiss could also make a great pair. Gray with his ice - make magic and Weiss with her ice - based semblance could have some really cool interactions. They could compare and contrast their ice powers, and perhaps even combine them in some creative ways during battles. Plus, their personalities are quite different which would lead to some interesting character development moments.
I think Naruto and Lucy would be really interesting. Naruto's brash and determined nature combined with Lucy's more level - headed and strategic thinking could lead to some great interactions. Also, Naruto might be fascinated by Lucy's celestial spirits.
Goku and Natsu would be an interesting pairing. Natsu is all about passion and brute strength in his use of fire magic, and Goku has his Saiyan power and love for a good fight. They could have some epic battles together, like sparring to see who's stronger, and also team up to take on tough enemies. They both have a bit of a reckless streak too.
Naruto and Natsu would be a really interesting pairing. Both are hot - headed, determined, and have a strong sense of justice. They would probably start off butting heads but then realize they have a common goal and work well together. Their powers are also quite different, with Naruto's ninjutsu and Natsu's fire dragon slayer magic, so they could combine their attacks in creative ways.
Ben and Natsu would be an interesting pairing. Natsu is all about fire and brute strength, while Ben has the ability to transform into various aliens with different powers. They could have a friendly rivalry, like who can defeat an enemy faster. Ben could show off his alien forms to Natsu, and Natsu could teach Ben some fire - based magic tricks in return.
Spyro and Natsu would be an interesting pairing. They both have a connection to fire. Natsu is a fire dragon slayer, and Spyro can breathe fire. They could have some epic battles together or team up against a powerful fire - based enemy. Another interesting pairing could be Spyro and Lucy. Lucy has her celestial spirits, and Spyro's otherworldly nature could add an interesting dynamic to their interactions.