Growing up as a predominantly PC gamer, boss fights used to make me nervous. I distinctly remember playing Super Mario World 2: Yoshi's Island at my buddy's place and handing him the controller for even the first boss, an encounter which involves a big guy jumping around until you hit him enough times for his pants to fall down. Looking back now, I didn't appreciate that the Kilrathi aces in Wing Commander, enemies like the Barons and Cyberdemons in Doom, or the Dark Jedi in Jedi Knight, were bosses too. Bosses always seemed like something that required real video game expertise to beat, something I just didn't have as a weekend gamer.

As an adult, I fully embrace the thrill of fighting a boss. The unique designs, the larger-than-life size, the new patterns, the initial panic that gives way to calm precision as you discover their weaknesses: it's one of the best things about video games. Hidden and secret bosses are major features of Japanese role-playing games like Final Fantasy, extra challenges for intrepid players deliberately hidden away to avoid the unprepared from stumbling upon them. The specific, often arcane, requirements for unlocking these foes present major challenges themselves and, once encountered, provide a challenge far beyond just "do as much damage as possible." Elemental resistances, spell reflections, and the dreaded Instant Demise all await those who would challenge these "superbosses."

While these are mostly pulled from JRPGs, there are the occasional bosses tucked away in every genre, from beat-em-ups to first-person shooters. Here is a list of the 25 best, trickiest, and most creative secret bosses. Good luck!

25 Emerald Weapon - Final Fantasy VII

This is the first thing that comes to mind when I think of a Secret Boss. Playing FF7 in the nineties was my first exposure to the JRPG-style gameplay and the idea of hidden content at all, not just the secret rooms of Doom, was surprising.

Fighting Emerald Weapon requires your characters to at the very least have their health maxed out at 9999 HP and for you to have mastered the infamous "Knights of the Round" summon. Even then, the Emerald Weapon fight is on a time limit, because he's frickin' underwater!

24 Naydra - The Legend Of Zelda: Breath Of The Wild

For all its spectacle, few moments in Breath of the Wild are as breathtaking as the first time you spot a dragon. Accompanied by a mournful song, the dragons snake through the air, unconcerned by the player, who is likely furiously trying to get within bow range to farm them for their scales and horns, which are powerful upgrade materials.

The ice dragon Naydra, however, isn't flying freely like her sisters. She's been corrupted by Ganon and is tethered to her mountain. Freeing her requires an exhilarating, madcap flight around that mountain, riding updrafts and dodging attacks to snipe the corruption tumors along her body.

23 Secret Blackreach Dragon - Skyrim

Technically, this dragon's name is "Vulthuryol" because Skyrim's dragons all sound like prescription medications with horrible side-effects.

Vulthuryol may cause immolation.

Skyrim's main quest takes the Dragonborn to the Blackreach, a gorgeous underground city built into a massive cavern where bioluminescent mushrooms light up the ceiling like stars. Dominating the area is a giant golden orb. If the Dragonborn casts Unrelenting Shout at the Orb, it'll ring like a bell, summoning Vulthuryol. Ol' Vulthy is one of many hidden bosses in Skyrim, in case you were looking for an excuse to buy it again.

22 Ruins Of Hornburg - Octopath Traveler

The recently released Octopath Traveler is a love letter to the Chrono Trigger and FF6-era of Square JRPGs, so it's no surprise that it also includes a hidden, secret boss. While there are 4 hidden bosses at the end of hidden shrines, which give the party access to super powerful extra jobs, Ruins of Hornburg is a dungeon that only opens up after you finish the main story.

Or, rather, finish all 8 stories.

Ruins of Hornburg serves as a sort of epilogue to Traveler, tying a lot of the stories and hints at larger lore together and dropping big winks towards a sequel.

21 King Yama - Spelunky

Part of what made Derek Yu's Spelunky was the sheer amount of hidden content in the game. Similar to how players of Dark Souls have spent years uncovering not just hidden locations and enemies but even whole mechanics hidden in plain sight, Spelunky has inspired a passionate fan base.

As is often the case with the bosses on this list, King Yama represents the 'true ending' of Spelunky. A giant dude in a chair who takes up most of the screen, appearing at the end of a hidden level, it is possible to destroy him or, if you try really hard, turn him into a sweaty eggplant.

20 Reptile - Mortal Kombat

In the era of YouTube and GameFAQs, it's hard to imagine what learning a new fighting game was like in the 90s. First, you had to physically go to an arcade, then spend real money, then just flail around to find a character's special moves. Mortal Kombat, with its post-match finishers, was built for secret hunting and I remember kids trading rumors at recess about hidden characters and secret codes.

Reptile would jump in between fighters before the beginning of fights and drop cryptic clues about how to find him: Getting a double flawless victory, in single player, then doing the uppercut finisher on The Pit level.

19 Slot Machine - Star Fox

Appropriately for StarFox, this hidden boss isn't just hidden from the regular gamepath, but from time and space itself! In the level "Asteroid Belt - Route 3" of the SNES game, Fox will fly by two massive asteroids. Shooting the rightmost one will cause an origami bird to emerge. Flying into it (But not shooting it!) Will cause Fox to be teleported to the level "Out Of This Dimension." The level is so weird it's best seen for yourself and ends with the most dastardly boss in the game: A giant slot machine.

18 Ballos - Cave Story

Cave Story is one of the earliest and most successful of the 16-bit throwback platformers. It paved the way for modern classics like Shovel Knight and Celeste, and is especially remarkable for being made by one guy, Daisuke "Pixel" Amaya, over five years. Cave Story is a Metroidvania with a surprisingly dark and well-written story.

Encountering Ballos requires completion of a sidequest that runs through the entire campaign. During the escape sequence after defeating the final boss, players who have successfully restored all of Curly's memories will gain access to the secret area, and the fight with Ballos.

17 Mega Hunters - Mega Man X2

Mega Man is practically built around the appeal of hidden content: its entire gameplay system is designed around finding which weapons work best against which boss. Mega Man X added other layers with hidden rooms that could only be accessed with certain powers, and even levels that change based on which Mavericks have been defeated when the player enters them.

X2 has three hidden optional bosses that appear once you've defeated your second Maverick. Challenging them requires finding their hidden rooms in the remaining 6 levels. Once you defeat them, you get a piece of Zero's armor, which saves you the headache of having to fight him right before the final boss.

16 Amygdala - Bloodborne

This one is especially close to my heart because it is the only boss on this list I discovered on my own, without even looking for it. Through a complicated sequence of bringing the right weird-named item to a place that inexplicably ends you without it, you're transported to a huge, totally optional area. Waiting for you at the end of it is… A pizza?

A giant brain with a spider body. Amygdala is one of the Old Ones, the same creepy beings that can be glimpsed clinging to the sides of buildings if your Insight is high enough.

15 Cow King - Diablo 2

A classic hidden boss, the Cow King is the result of a years-long rumor started with the original Diablo. People said you could click on a cow in the fields outside Tristram to teleport you to a secret area. It wasn't true. Blizzard even included a cheat code for StarCraft, "There is no cow level," proving it. But then, on April 1st, 1999, they posted a screenshot showing two cows fighting. When the game released, players used the Horadric Cube to combine items and eventually discovered the fabled Secret Cow Level.

14 Cake Boss - Assassin's Creed: Unity

Assassin's Creed: Unity is a gorgeous recreation of Revolutionary France, with a staggering attention to detail that makes the game more fun to just walk around in than actually play. Explorers will find hidden around Paris, five pink cakes. Making Arno eat each one will spawn a giant cake in the middle of the garden of the Luxembourg Palace. Standing atop this cake is the Cake Boss who will fight you to grave if you approach him, triggering a fireworks display.

13 Moon Prescence - Bloodborne

As stated above, Bloodborne is a beautiful modern game steeped in old school traditions. Meaning it is super hard, doesn't explain itself very well, and its story is hidden in the margins, forcing you to go looking for the real reason you're ending werewolves.

As if you need one.

It's possible, through a ridiculously complicated series of events, to find hidden items called "One Third of Umbilical Cord." (Though there are actually four). Consuming the full cord will allow you to fight the Moon Presence, the Great One who has been secretly manipulating Gehrmann, your wheelchair-bound buddy, all along.

12 Driviks - Destiny

Destiny was packed full of hidden items, areas, enemies, and lore, instead of a cohesive narrative. Similar to an MMO, most players will never see some of Destiny's best content, gated as it is behind group events or endgame content, or just a sheer cliff of a skill requirement.

Driviks only appears occasionally in the "Heroic" (Read: hard mode) version of a story mission from The Taken King expansion. Players have a strict time limit with which to take him down but are rewarded by Black Spindle, a sniper rifle that auto fills its magazine if you get headshots with all three rounds.

11 Adamantoise - Final Fantasy XV

After finishing the main quest of Final Fantasy XV, there might not seem to be much the player's group of RPG Monkees can't handle, so the game throws a mountain at them.

A mountain which is also a turtle.

Adamantoise, according to the game's bestiary, is the largest and oldest living creature known to man, so of course, your team has to go end it and make food out of it. Early reports said the fight would take 15 hours and, while the actual fight is not that long, the beast still has a staggering 5 million HP.

10 Culex - Super Mario RPG

Square and Nintendo's beloved experiment, Super Mario RPG, is a strange blend of the two companies' styles and sensibilities but is mostly more Mario than Final Fantasy. Culex, the strongest boss in the game, is the opposite: he's a 2D sprite from another dimension who wishes to battle the weird 3D creatures of Mario's reality. In his presentation, dialogue, and even the music that plays when he's around, he seems to be a direct transportation from Final Fantasy.

9 Ender Dragon - Minecraft

In 2009, Minecraft creator Notch started musing about the game having a real end goal, instead of just surviving for as long as possible. That goal became The End, a dimension accessible only by gathering several End Stones and creating a portal that transports you to a lightless world, where you can summon the Ender Dragon. Defeating it gives you a ridiculous amount of XP (12,000) and a dragon egg which is the most unique block in the game, spawning only once per world.

8 Yiazmat - Final Fantasy XII

Yiazmat is the final Elite Mark in Final Fantasy XII, meaning the players have to make their way through the entire hunting subquest to get a chance to fight it. Hopefully, that means the player's party is a high enough level to challenge the beast, because this marble-clad portal dragon has over 50 million hit points.

Yiazmat is not only the God of all Dragons, but he's a classic FF ultimate boss: every one of his regular attacks has a 5% chance of instantly ending whatever they hit, and the closer to demise he gets, the higher the chances he'll completely heal himself.

7 Baron K. Roolenstein - Donkey Kong Country 3

Packed as this list is with RPGs both new and old, don't get the idea that hidden, secret, and super-tough bosses are the property of games with XP and inventory screens. Donkey Kong Country 3 has a secret boss of its own in the Knautilus, an escape submarine hidden under the waves that serves as the true final boss fight of the game.

After beating the Krematoa levels and cashing in all five cogs, the sub will be revealed to Dixie and Kiddie, where Baron K. Roolenstein is waiting.

6 The Final Boss Is You - Pokémon Gold & Silver

After beating either Pokémon Gold or Silver, Professor Oak will give the player permission to access the "secret area" at the summit of Mt. Silver. Waiting for you at the summit of the mountain is Red, the very same trainer we played as in the very first Pokémon, Red & Blue, way back on the original Game Boy.

Red is loaded with a nostalgic overload of original Pokémon, starting, of course, with Pikachu, but including all the classics from Charizard to Blastoise and even my man Snorlax