The 14 Greatest Final Forms in Anime History

Mirajane Strauss uses a powerful technique called Take Over, which allows her to 'take over' the skills and physical attributes of other beings. While many people use Take Over, Mirajane is one of the few who can use Satan Soul, which allows her to assume the form of four different demons. The most powerful of these forms is Mirajane Alegria, which Mirajane was able to assume when she consumed all of the souls that resulted from defeating Tartaros.

The sheer magical energy of this form is terrifying: it's enough to evaporate an ocean by her simple existence. Besides that, her form creates a gargantuan boost in speed and strength. Mirajane can't keep up the form for long, as it requires a ton of magical energy and is phyiscally exhausting. 

Considering how much Cell brags about the superiority of his final form, he'd better actually measure up to his claims. While he's not totally indestructable in his new form, he gives everyone who tries to take him on a run for their money. He gets there by absorbing Androids 17 & 18. As Perfect Cell, he can teleport, regenerate, create clones of himself, replicate other people's powers, and more. Even warriors as powerful as Goku and Vegeta struggle to defeat him. Ultimately, Cell decides to self-destruct when he realizes that he can't win, which prompts Goku to use instant transmission to bring Cell to King Kai's planet and save the Earth - sacrificing himself in the process. When Cell regenerates, however, it's Gohan who ultimately ends up finishing the job.

Father's first form, the Dwarf in the Flask, isn't capable of much - but oh boy is he burning with ambitions. After achieving a series of increasingly powerful forms, he finally manages to achieve his final form by absorbing a higher power that he refers to as "god."

Now as strong as he'll ever be, he can perform alchemy without sacrificing something of equal value - which means that he can do literally anything, which includes creating a miniature sun that he can hold in the palm of his hand. His powers don't last long, but they certainly make an impression while they're around.

Madara Uchiha was always stupidly powerful, even when he was just a regular Konoha ninja. Though he was never hokage due to his personality problems, he was certainly powerful enough to qualify for the role. He undergoes several major changes over the course of the series, including passing away and reviving himself, and being biologically modified by Kabuto to increase his power. Eventually, he becomes the Ten Tails Jinchuuriki, which means that he's powerful enough to contain the strongest Tailed Beast of them all. In addition to acquiring a wide range of abilities like flight and Truth Seeking Balls, Madara gains the power to cast Infinite Tsukuyomi - a powerful genjutsu that would put the entire planet into a state of hypnosis.

When Sousuke Aizen first appears, he seems to be a mild mannered nerd who wouldn't hurt a fly. Not only is that not his true form, it isn't his final form, either. Using the power of the Hogokyu sphere, he eventually reaches his final form. In this form, he has all of the powers granted by the Hogokyu, which include super strength, speed, and endurance, teleportation, and regeneration. His final form adds a new ability: the Hollow-like skulls on his wings can blast spheres of energy at his opponents. The fact that anybody managed to defeat this guy is truly stunning. 

Digimon is all about increasingly powerful evolutions, so it's hard to say that any given form is "final." That's part of why Omnimon of Digimon Tri, a series that is likely the final edition of the Digimon Adventure saga, is easily one of the best. That and the fact that they're a combination every mega evolution that the Digidestined had on their team into the Holy Knight Digimon, Omnimon Merciful Mode. Basically, they're a revamped, angelic version of the original Omnimon, who can lay waste to their opponents using a shining blue blade.