1. Ashura: Ashura, the son of the Six Paths Sage, and Naruto, who is his reincarnation, have different levels of lineage. Ashura's Rasengan is more powerful than Naruto's as it has multiple cores.
2. Jiraiya: Jiraiya, Naruto's master, taught him Rasengan. While Naruto surpassed Jiraiya, Jiraiya's Rasengan is larger and has a fire attribute, making it stronger.
3. Hashirama Senju: Hashirama Senju developed Rasengan but couldn't perfect it due to the Nine-Tails' attack.
4. Momoshiki: Momoshiki, a character in the Naruto movie, uses a black Rasengan that is smaller but exceedingly destructive. If Momoshiki could enlarge its size, it could potentially destroy the ninja world.
5. Boruto: Naruto's son, Boruto, learns Rasengan and can already throw it and make it invisible. With his Jougan, Boruto's Rasengan will likely surpass Naruto's, and he may develop new versions.