His summons should be direwolves sinces he has fire and direwolves live in cold harsh environments it will make his fire element stronger and he could also create new jutsus if he has more control over fire If you dont know about direwolves you can take a reference from this fanfic : Naruto the uchiha prodigy
ch 13 Chapter 13
Anime & Comics · Fire_Phoenix_02
What is name of your other uchiha fic
Konoha no KamiKaze
Anime & Comics · RedRest0