Some gamers aren't satisfied with the core game's challenges. To combat this desire for a challenge some video game developers provide an extra secret boss fight that tests the player's mettle and skills. Here are the top 5 best secret boss fights in video games.

5. Super Mario RPG: Legend of the Seven Stars - Culex

Considered one of the best Mario games of all time Super Mario RPG: Legend of the Seven Stars was a gem among the SNES library. Developed by Square Enix this titled featured the time battle mechanics later introduced in the Mario and Luigi handheld games. Although the final boss Smithy was already a formidable challenge Square Enix decided to add an extra even harder boss.

Culex, Dark Knight of Vanda can be found in Monster Town. This dangerous opponent is clearly inspired by the Final Fantasy series. Culex has the second most health of any encounter in the game and is guarded by 4 Crystals. If you wanted a challenge, Culex was that challenge.

4. The Elder Scrolls V: Skyrim - Karstaag

Getting to the secret boss is usually half the battle. In Skyrim, the hidden boss Karstaag requires a journey just to face him. You must trigger an unmarked quest called "Summoning Karstaag" by obtaining a skull from the Glacial Cave. Next, you have to get to the Castle Karstaag Ruins, which requires master unlocking and place the skull on the throne.

What follows is an intense battle against the strongest enemy in the game, even more than the Ebony Warrior. Karstaag can inflict frost damage at a constant rate, requiring high magic resistance. On top of it, Karstaag is immune to all frost, poison, and paralysis damage and to most of your Dragon Shouts. Killing the creature will allow you to summon the creature 3 times but since you already killed the strongest enemy in the game the reward doesn't really matter.

3. Kingdom Hearts - Sephiroth 

The legendary One-Winged Angel from Final Fantasy 7 was a memorable fight, so Disney and Square Enix decided to give Sora a chance to fight the 1st Class Soldier. After 100% the game and beating all the previous cups in the Coliseum you're given the chance to fight Sephiroth.

As you might expect, it's not easy. Sephiroth is decked out with powerful physical and magical attacks. You can't even hurt him until Sora eliminates his shielding. With multiple ways to kill Sora in 1 hit, this fight is not for the weak hearted. His fight in Kingdom Hearts 2 isn't any easier but considering that his encounter in Kingdom Hearts 1 was well hidden and only available to the most dedicated players. It was a well earned and remarkable battle.

2. Mortal Kombat - Reptile

Before access to the internet became common rumors about hidden secrets irked the schoolyard. Some true and others not. Things such as Mew's location behind the truck of the SS Anne and the green ninja in Mortal Kombat. Turns out the latter was true.

The green acidic ninja was possible to fight but only with specific requirements. Players had to see silhouettes gliding past the moon at the Pit stage (this will occur every 6th game), achieve a double flawless victory, never press block, and execute a fatality to face off against the mysterious green ninja.

The ninja was named Scorpion in the game but would later be given his own name and identity. Hence now known as Reptile.

1. Final Fantasy XII - Yiazmat

The Final Fantasy series is notorious for having challenging secret super boss fights. Yiazmat is one of the hardest and longest fights in the Final Fantasy series. 

Only made available at the end of the Hunt quest line in Final Fantasy XII this creature has 3.7 million HP. At first, it seems that Yiazmat is just a huge bullet sponge but that eventually changes. With each bar of its health increasing the beast's power and defense. The bright side you can leave the arena and begin where you left off. The bad news is that it can cast Renew and you run the risk of it recovering all its health.

The fight was already difficult. But those who played The Zodiac Age will find the updated version of Yiazmat to be even harder due to the player's restrictive access to specific class types.

What are your favorite hidden boss fights? Let us know in the comments below!

Adam Siddiqui, NoobFeed
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