There are three things that make an RPG truly memorable - its music, story, and boss fights. A boss, no matter if they are the first mini-boss or the final big bad, is supposed to be a challenge and a point where players can test the skills they have learned against a foe far stronger than any enemy they had faced.

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A boss should also be unique, not just a challenge. Although difficult bosses are memorable, the ones that truly impact players are the ones that do things differently. They introduce new and interesting mechanics. They flip the script on the player's morality. They have a compelling backstory and motives.

8 Axel - Kingdom Hearts II

Kingdom Heart II: Roxas And Axel's Final Confrontation

While not the final boss of this game or even one of the most difficult, Roxas' fight with Axel cements itself as one of the most memorable. For one, the fight is visibly striking as Axel summons a literal ring of fire around him and Roxas, trapping them in a ring and forcing a fight between the two former friends.

However, what truly makes this fight one of the best is the impact behind it. While players get a glimpse of Roxas and Axel's shared past leading up to this climactic duel, the depth of their bond doesn't truly reveal itself until a later game. Once these truths are revealed, this final fight becomes all the more heartbreaking. You also get to use two Keyblades for the first time in the series, so bonus points there.

7 Kefka - Final Fantasy VI

Final Fantasy VI: Kefka Stands Against The Party

Many find multi-stage boss fights annoying and tedious due to their repetition. Most of the time, such bosses merely come back with more health and stronger attacks. This is not the case with Kefka.

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While not as iconic as the One-Winged Angel Sephiroth, the Kefka left his mark on players with his variety of attacks and spells that trigger depending on the state of his health bar. What's more, aside from simply spamming powerful attacks, he will also inflict statuses such as Bind and Silence. You're going to need a good strategy for this fight.

6 Shadow Kanji - Persona 4

Persona 4: Shadow Kanji True Form

Like many of the bosses in the Persona series, there is more to Shadow Kanji than just an oddly preportioned bodybuilder. As a Shadow, Shadow Kanji represents the hidden emotions of Kanji Tatsumi, specifically his fears of being viewed as too effeminate, translating into a flamboyant Shadow.

After an admittedly difficult fight, Kanji rejects his Shadow, leading to an emotional outcry for the Shadow as he desperately asks if anyone would accept him. While Kanji eventually accepts his Shadow, it's still heartbreaking to realize that Kanji craves acceptance more than anything else.

5 Malos: Xenoblade Torna - The Golden Country

Xenoblade 2: Malos Challenges Mythra

The Torna DLC advertised itself as the retelling of the Aegis War that had been mentioned in Xenoblade 2, leading up to the climactic final fight between Mythra and Malos. The dark and stormy backdrop sets the perfect stage for this final encounter as both Mythra and Malos summon their respective mechs, or Sirens, and clash for what they assumed would be the last time.

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This battle takes away the standard Chain Attack mechanic and replaces it with the Siren Gauge which, once filled, allows you to attack with the massive mech for devastating, and cinematic, attacks. The trade-off for such a powerful ability is that Malos also controls his own Siren and also has a gauge to fill. Should he attack first, he can seal your party meter. Say what you want about his character, but this fight with Malos is one that no Xenoblade fan will soon forget.

4 Cynthia - Pokemon Brilliant Diamond And Shining Pearl

Pokemon Brillian Diamond And Shining Pearl: Cynthia Accepts Your Challenge

When it comes to Pokemon Champions, Cynthia has always had a certain aura about her. Whether it's her theme or her appearance, she's always demanded respect. While many argue about which Champion is the strongest, Cynthia is certainly the most diverse.

Until Gen 4, the Pokemon League Champions have always stuck with one type or theme with their teams, such as Lance's dragons and Steven's Fossil and Steel types. Cynthia is the first one to deviate from this, possessing a rather diverse and frankly terrifying team, making it far more difficult to prepare for her than any other Champion before her. This is especially true if you fight her for a second time.

3 Giygas - Mother

Mother 1: Giygas' True Form

Debatably one of the most interesting antagonists within the Mother franchise, Giygas proved himself to be more than a simple villain. With a backstory not dissimilar from that of Superman, you actually feel for Giygas, then referred to as Giegue. Even as you fight him, you can't help but feel bad for the alien and the situation he's been put in.

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What's more, you don't even win this fight. Giygas proves too powerful for you and your party. The only way to win is to sing a lullaby that was sung by Giygas' foster mother. Remembering his humanity, Giygas spares the party and leaves, only returning in the sequel game and proving, once again, to be a difficult and tragic enemy.

2 Orgodemir - Dragon Quest VII

Dragon Quest Scan Battlers: Orgodemir Laughs Maniacally

As the main antagonist of Dragon Quest VII, Orgodemir's presence is known far before his actual appearance. He manipulates others into doing his bidding, attempts to steal the abilities of other adventures for himself, and even traps the hero and his party in a block of ice. However, all of these are nuisances in comparison to when he overtook the Almighty.

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That's right, this Demon Lord defeated this world's god and took his place, continuing his machinations, but from a higher standing. Thankfully, the hero's party doesn't fall for this deception and manages to confront the demon, leading to a difficult fight and a terrifying transformation.

1 Asriel Dreemur - Undertale

Undertale: The God Of Hyperdeath's Relentless Barrage

While the title of the most difficult boss fight of this game remains with Sans, the "true" final fight still stands up. Easily one of the most difficult fights, Asriel has a plethora of different attacks to keep players on their toes and, while he can't kill you, it can be incredibly difficult to precede to his final phase.

Keeping to the Pacifist Route, instead of fighting back, players are meant to save those that Asriel had absorbed to defeat this newly minted god. Once all these souls are free, the only one left to save is Asriel, leading to an intense battle and heartbreaking dialogue.

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