When it comes to most video games, it is common knowledge that players must advance through the game by defeating bosses at the end of each stage. For those willing to test the limits of their skills as gamers, the biggest thrill comes from going out of their way to challenge hidden bosses.

In fact, some games contain optional bosses that can be found outside of normal gameplay. In most cases, these bosses are extremely powerful and require players to at least beat the main game to be eligible to face them. When it comes to these secret bosses, it is possible for them to be hidden in plain sight.

On the other hand, most are so well hidden, that players must go out of their way to discover their locations. To find them, players must often complete additional tasks. These can range from performing certain actions on your controller, acquiring hidden items, or even discovering maps and information leading to these hidden locations. Once this is done, the hidden bosses will be revealed, and the fight can begin.

Most of the time, players can expect a tough fight when it comes to hidden bosses. However, this is not always the case as some hidden bosses can be included just for fun or comedic effect. These bosses may even serve as a reference, or even pay homage to games from other franchises.

Without further ado, here is a list featuring 25 Hidden Bosses in Video Games and Where To Find Them.

Cow King: Diablo 2

As far as most bosses on this list go, the Cow King is by far the most unusual. In the first Diablo, the concept of the Cow King was initially created as a joke. Eventually, the developers went and included the Cow King as a hidden boss in Diablo 2.

However, this boss cannot be accessed by normal means.

The player must travel to the secret “cow floor”, to have a chance at this elusive boss.

If the player leaves him alone, the king will spawn endless cow minions for players to fight. However, defeating the Cow King will cause the player to lose access to the floor.

Gold Tyrant: Resident Evil

The Tyrant has long been recognized as one of the Resident Evil franchise's most iconic monsters. For those lucky enough to possess the Sega Saturn version of the original Resident Evil, players have a chance to face the Gold Tyrant.

The Gold Tyrant is an optional boss that can only be encountered in the Sega Saturn’s exclusive “Battle Game” feature. In this mode, players must defeat waves of enemies with limited ammunition as they advance through each stage.

Upon reaching the final stage, players will face the Gold Tyrant, which is even tougher than the original version. When you are facing this type of foe, conserving ammo has never been more important.

Sephiroth: Kingdom Hearts 2

Sephiroth Kingdom Hearts model

Sephiroth is an optional boss in Kingdom Hearts II. As one of the strongest bosses in the game, Sephiroth possesses 15 health bars, and can deal massive damage leaving little time to launch a counter attack. This makes him an ideal opponent for dedicated to test their skills.

After beating the stage “Space Paranoids", it becomes possible for the player to fight Sephiroth.

He can be found in the Dark Depths overlooking the canyon on the outskirts of Radiant Garden.

It is preferable to fight him after beating the game, and also after you acquire the strongest weapons and abilities.

Valkyries: God of War

As part of a side quest in God of War, Kratos must find and defeat the eight Valkyries. Unfortunately, it takes a little effort to find them as they are hidden in secret locations throughout the nine realms.

Four of these Valkyries are found in Midgard, while the other four can each be found in Muspelhiem, Helheim, Niflheim, and Alfehim. After defeating them, Kratos will not only get rare items and upgrade materials, but the Valkyries remain as well.

After obtaining all eight of the Valkyries remains, Kraots must bring them to the Council of Valkyries in Midgard. Once this is done, Kratos can challenge the queen of Valkyries as a bonus.

Culex: Super Mario RPG Legend Of The Seven Stars

Super Mario RPG Culex Battle

When you combine the visuals of the Super Mario franchise with the RPG elements of Final Fantasy you get Super Mario RPG: Legend of the Seven Stars.

One of the most interesting things about the game is its secret hidden boss, Culex.

To find Culex, the player must travel to Monstoro town.

There they will find a door in a mountain that leads to Culex’s dimension. However, the player must first travel to Moleville to purchase fireworks. Afterward, they must trade it with a little mole girl to get the shiny stone.

Once this is done you are free to challenge Culex.

Morgan Freeman: South Park: The Fractured But Whole

In South Park: The Fractured But Whole, you can expect to fight some pretty unusual bosses. One of the game's strongest bosses just so happens to be hidden in plain sight.

Who is it you may ask? It’s Morgan Freeman. To fight him, the player must travel to his restaurant, Freeman Tacos, where he also helps you to unlock new powers.

Challenging him does not require any complex requirements. All it takes to start a fight with him is going around the counter and hitting him a couple of times. However, it’s best to avoid upsetting him until after you’ve beaten the game and unlocked all your abilities.

Noob Saibot: Mortal Kombat

When it comes to Mortal Kombat, the series has no shortage of brutal characters. In Ultimate Mortal Kombat 3, one of the strongest characters the player can choose to fight with is Noob Saibot.

Although officially, Noob Saibot’s first appearance was in Mortal Kombat II. He appears as just a black silhouette and is a non-playable character. Still, it is possible for players to fight him.

There is a chance that he will appear in the Goro’s Lair stage after the player wins 50 matches in a row.

However, once he appears, one must be ready for the most challenging fight in the game.

Giga Bowser: Super Smash Bros. Melee

In Super Smash Bros. Brawl and Super Smash Bros. for Nintendo 3DS and Wii U, Bowser possesses a terrifying power for his ultimate move.

As part of his Final Smash, Bowser will transform into the near unstoppable monster known as Giga Bowser. Fortunately, it is possible to face Giga Bowser as a boss in Super Smash Bros Melee.

However, to fight Giga Bowser, the player must clear adventure mode in under 18 minutes on normal difficulty or higher. If the player can successfully defeat him in one go, they will receive his trophy as a prize.

Ethereal Queen: Star Ocean Series

In the Star Ocean series, the Ethereal Queen is considered one of the strongest bosses in the franchise.

The requirements needed to face the Etheral Queen will vary depending on the game.

In Star Ocean 2, the player must acquire the Silver Trumpet after defeating the main boss, Gabriel Celesta, and must play it with a music level of 10. However in the third game, the queen is located on floor 211 of sphere 211. Finally, in the fourth installment she is found on B20 of the Wandering Dungeons.

Regardless of which game the queen appears in, players will have a tough time defeating her.

Emerald Weapon: Final Fantasy VII

Final Fantasy VII Emerald Weapon

Final Fantasy VII has two hidden bosses that are infamous among gamers. Emerald Weapon just so happens to be one of them. Both Emerald Weapon and its counterpart, Ruby Weapon, are hidden bosses that are unlocked only after the player fights Sephiroth and beats the game.

After Sephiroth casts Meteor, the player can hunt down these ancient weapons. Unlike Ruby Weapon, which can be found on land, the player must travel below sea level to find Emerald Weapon.

After acquiring the Shinra Sub, the player can search for Emerald Weapon in the inland sea.

Slot Machine: Star Fox

Star Fox Out of This Dimension Slot Machine

To confront the Slot Machine, the player must first enter the hidden “Out of This Dimension” stage.

To reach this stage, players must take the third route and reach the “Asteroid Belt”.

Once there, the player must fly by an asteroid on the left side of the screen. After passing by a second asteroid, the player must destroy it to release a bird-like origami creature.

If the player leaves it alone and rams it, they will be transported to the Out of This Dimension stage, where they will eventually face the Slot Machine. Unfortunately, upon entering this dimension it is impossible to leave.

Never has a "game over sounded so good.

The Wither: Minecraft

By all accounts, the Wither is the strongest boss character that any player will face in Minecraft. Unfortunately, summoning a Wither requires a bit of effort on behalf of the player and a trip to the Nether.

A Wither summoning requires four blocks of Soul Sand and three Wither skeleton skulls. After placing the skulls on the blocks in the shape of a T, the Wither will materialize.

However, players must be well prepared to fight a Wither. Not only does it explode and destroy the blocks around it, it also constantly regenerates.

The Nameless King: Dark Souls III

In Dark Souls III, most people will often overlook the importance of Archdragon Peak. It is there where the player can confront the Nameless King. As an optional boss, the Nameless King can be summoned by performing a certain action.

However, considering his level of difficulty, its preferable to take one’s time and get stronger before summoning the Nameless King.

Once the player is ready, they must head to Archdragon Peak, and ring the bell.

Doing this will summon not only the Nameless King, but his dragon mount, the King of The Storm. The player must defeat both to emerge victorious and claim the worthwhile rewards.

Emil Lv. 99: Nier Automata

Players who are familiar with the original Automata will no doubt recognize Emil. Despite his appearance, Emil is a secret boss that the player can fight with after having completed the game, acquired the hacking ability of 9S, as well as completed the “Lunar Tears” side quest.

Once these requirements are fulfilled, it becomes possible to access Emil’s house, located in the Desert Zone’s City Ruins: Center Crater. While there, the player must steal one of Emil’s masks and return to him. Afterward, the player must return to the house again, which will trigger the boss battle.

At level 99, those who take on Emil must not underestimate him.

Naydra: The Legend of Zelda: Breath of the Wild

In The Legend of Zelda: Breath of the Wild, the dragon Naydra, along with the dragons Dinraal and Farosh, is one of three possible dragon bosses that Link can face.

Despite Dinraal being the easiest of the three dragons, Naydra is essential to teaching Link the basics of aerial combat.

Before facing Naydra, it is important for the player to be equipped with a frost resistant outfit like the Snowquill.

Naydra will be waiting on the peak of Mt. Lanaryu. Once the battle starts, Link must navigate using nearby updrafts to paraglide through the area and bring Naydra down using arrows.

Phantom: Kingdom Hearts

Among the many Heartless in the Kingdom Hearts series, none are more frustrating to beat than the Phantom. This boss from the first game can only be found in the Neverland stage.

After sealing the keyhole in Hollow Bastion, the player must return to Captain Hook’s ship in Neverland. After talking to Peter Pan and Tinkerbell, the latter will ask if Sora wants to go to the Clock Tower.

Saying yes will bring Sora and his allies to the Clock Tower, where the Phantom awaits their arrival. Once the battle starts, be prepared for an intense fight that requires precise timing and a ton of MP-restoring items.

Karstaag: Skyrim

By the time you begin your journey in Skyrim, the frost giant Karstaag is already long gone. However, fear not: it is still possible to face this mighty creature as a secret boss.

To fight him, head to Castle Karstaag where his remains sit on a ruined throne.

Unfortunately, a key item is required to summon forth Karstaag: his skull. Thankfully, it can be found in Glacial Cave which is not too far from Kaarstag’s castle.

After bringing the skull to the remains in the castle, Kaarstag’s spirit will manifest, ready for a fight. Upon defeating him, the player can summon him up to three times (for outdoor use only).

Akuma: Super Street Fighter II Turbo

In Super Street Fighter II Turbo, Akuma makes his first appearance as a potential boss. However, he cannot be challenged through normal means.

For starters, Akuma can only be challenged in single player mode. Secondly, the player must defeat all eight preliminary opponents, as well as Balrog, Vega, and Sagat. Finally, this must all be done either within 25 minutes before the final match or by achieving a high score without any continues.

Once these conditions are met, during the final match against M. Bison, Akuma will appear. Upon his arrival Akuma will dispatch and replace him as the final boss.

Lingering Will: Kingdom Hearts 2.5 Final mix

In Kingdom Hearts: Birth By Sleep, players are able to play as one of three Keyblade disciples: Ventus, Aqua, and Terra. Each of these disciples use a special Keyblade warrior armor. In Kingdom Hearts 2.5 Final Mix, Terra’s armor appears as a secret boss as the Lingering Will.

To fight the Lingering Will, the player must first beat the game and complete all worlds.

The player will return to the Hall of Cornerstone in Disney Castle, where a portal will appear.

Upon entering the portal, Sora will be transported to the Keyblade Graveyard, where the Lingering Will awaits.

Rodin: Bayonetta Franchise

In the Bayonetta franchise, Rodin is a close ally to the Umbra Witch Bayonetta.

Although he does not show it much during the game, he is an incredibly powerful being. In both Bayonetta and Bayonetta 2, it is possible to fight Rodin as a secret boss. In both cases, the player will need to purchase a platinum ticket which costs ten million halos. Once this is done, Rodin will happily fight you.

Depending on the game, the player will face a different version of Rodin. In Bayonetta, Rodin will fight you as Father Rodin. In the sequel, he will appear as Devil Rodin.