One of the best features video games have come to incorporate is rewarding a player appropriately for completing a challenge. The more challenging a task is, the better the reward, but not all games will utilize this mindset. Some challenges, like boss battles, offer little incentive for players to complete them and, sometimes, require far too much time and effort.

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Some gamers will embrace the challenges offered to them by a video game, but certain battles are slightly too difficult to be deemed enjoyable, especially when a game's previous challenges weren't nearly as tough. Difficulty spikes are a great way to mark progression, but sometimes they can derail a game's already solid flow.

5 Final Fantasy 15 - Penance

Final Fantasy Hardest Bosses Penance

The Final Fantasy series is renowned for featuring some of the most challenging bosses in gaming. The tenth entry in the series marked the beginning of a new era for the franchise with the addition of voice acting, but most of its core elements, like its combat system and challenging postgame, remained the same. Completing the main story will usually require the player to deal around 5,000 damage per hit, but vanquishing the game's secret enemies will require a damage output of approximately 99,999 to break through their armor.

Final Fantasy 10 is wrought with bafflingly tough bosses, but one outranks them all. Penance can only be fought after the Dark Aeons and the Monster Arena battles are all completed. The player may think they are invincible upon vanquishing these foes, but Penance will ensure to diminish this newfound confidence during the player's first encounter with it. The battle with Penance will usually last an hour, but only if the player has fully leveled their party members. Otherwise, this fated clash will likely end as quickly as it began.

4 Punch-Out!! - Mike Tyson

Mike Tyson centered in ring with fists up in Mike Tyson's Punchout

Punch-Out!! is a rhythm-based boxing game with a simple premise. Little Mac, the game's protagonist, is seeking stardom in the world of boxing and must battle his way through the World Video Boxing Association if he hopes to achieve it. Most of the game's fictional enemies pose little challenge in the boxing ring, but there is one who will likely leave fans furious. Mike Tyson, the actual heavyweight champion of boxing at the time, is the final boss and, understandably, the most difficult.

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What's unusual about the fight against Tyson is just how tough he actually is. There is no denying that certain fights in Punch-Out!! are quite difficult, but none of them hold a candle to the game's final battle. The boxing legend offers little room for error as most of his punches can instantly K.O. Little Mac and, to make matters worse, the player will seldom get an opportunity to attack. It is a surprisingly difficult encounter, made even more infuriating by how approachable the game's other battles are.

3 Kingdom Hearts 3 - Yozora

Yozora with weapon

The base release of Kingdom Hearts 3 offered surprisingly little in terms of a postgame, but the Re Mind DLC chose to remedy this. Featuring a whopping fourteen extra bosses, the aftermath of Sora's clash with Xehanort consists of some of the greatest challenges to appear in the entire series. Upon besting the data battles in the Limit-Cut Episode, however, Sora will be forced to face his most powerful enemy yet.

Yozora, briefly referenced in the Toy Box world, has been tasked with saving Sora in a somewhat unconventional way. Instead of explaining his reasoning, he summons his laser sword and crossbow and proceeds to attack Sora. It is likely players will expect a similar challenge to what they've already faced in the DLC prior to this battle, but Yozora proves to be one of, if not the most, challenging bosses in the entire series.

2 NieR: Automata - Emil

NieR: Automata, Emil

The first encounter with Emil paints him as one of the least threatening entities present in the NieR universe. He is a rolling head in a world full of war machines, so it is understandable why many would assume his combat skills would be lacking. This assumption, however, is quickly proven to be misguided upon attempting to steal the elusive being's prized possessions.

After having his home raided by 9S, Emil decides to stage a trap. He places his remaining trinkets in a chest and informs 9S that opening it would be extremely difficult. 9S takes the bait, and Emil, expecting this outcome, lunges, and attacks in an attempt to punish the overly curious android. At level 99, Emil poses the greatest challenge in the entire game. If his damage output isn't enough to deter the player from getting on his bad side, the tiny arena he is fought in certainly will. Though the next battle against Emil's clones is considered by some to be slightly more challenging, the player is given much more room to breathe thanks to the battle arena.

1 Final Fantasy 12 - Yiazmat

Final Fantasy Hardest Bosses Yiazmat

Final Fantasy 12 is chock-full of some of the most ridiculously powerful bosses in the entire franchise. The last boss the player will face will likely be none other than Yiazmat, the strongest boss and most elusive hunt in the entire game. The most efficient way to beat Yiazmat is to fully max out the stats of each party member, but the battle will still be ludicrously tough even then.

At max levels, Yiazmat will take around one hour to defeat due to its 50,000,000 hit points. Though the battle's duration may not seem like a big issue, it can quickly become arduous due to Yiazmat's ability to instantly K.O. a party member. Surviving the wyrm's longwinded onslaught for an hour is one of the fight's greatest challenges, but the player will have the option to leave the battle and heal up if they become overwhelmed. Going two screens away, however, will completely restore Yiazmat's HP, and force the player to start the battle from the beginning.

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