If layered, secret-laden games like Mass Effect, Skyrim, and The Legend of Zelda: Breath of the Wild have taught us anything, it's that some developers put incredible effort into things many players may never engage with or even see at all. On one end of the spectrum, you have amusing little Easter eggs - and on the other, entire games within games that you might not even know existed. What's more, the best of these mega-minigames seem like they can stand on their own (and in a few cases, have). We're not talking about existing games included as freebies, like Maniac Mansion tucked away in Day of the Tentacle, nor are these familiar card games offered as a distraction as in Red Dead Redemption or Far Cry 3. No, these are entirely unique titles, either hidden or presented as optional ventures, that play quite unlike the larger game that contains them. If you weren't aware these gems were there at all or you just never gave them the time of day, it's high time you found out what you've been missing (like Dead Ops Arcade 2, pictured above).
Demontower (Night in the Woods)
Platform(s): PS4, PC
For all its hilarious antics carried out by young adult animal people, deals with some pretty heady concepts about failure, uncertainty, and acceptance. It can be a lot to mull over - so if you need to give your emotional faculties and philosophical reasoning a rest, why not test your twitch reflexes for a bit? Once our hero Mae gets her laptop fixed, she'll find a complimentary copy of Demontower installed: a top-down, lightly randomized dungeon crawler starring a pale feline wielding a sharp sword. If you've played Hyper Light Drifter, Demontower's tight, dash-centric combat will feel instantly familiar, and it's just as tough thanks to an ingenious mechanic: every time you kill a boss and ascend to the next floor, you permanently lose one of your nine lives (that is, health bars) but gain an extra dash meter in its stead. The higher you go, the harder the challenge due to your increased frailty - but if you can achieve mastery of artful dodging, you just might make it through alive.
Grognak and the Ruby Ruins (Fallout 4)
Platform(s): PS4, Xbox One, PC
If you're a Sole Survivor looking to beef up your melee abilities in the Fallout 4 wasteland, you'd do well to seek out some Grognak the Barbarian comics, which have been chronicling the heroics of a muscular, half-naked Conan doppelganger since Fallout 3. Simply reading these comics will make you a better puncher, but Grognak's adventures really open up if manage to find his Pip-Boy-compatible game-tape tie-in hidden inside the Memory Den. This wrist-mounted RPG is a shockingly in-depth spoof on classics like Ultima, with party members to recruit, monsters to slay, an overworld map, and detailed sprite graphics that really make the most of the Pip-Boy's monochromatic green screen. Unless you somehow loathe riveting text descriptions of battle, this is easily the most impressive game in the Pip-Boy's library - and it's even got cartridge saves to boot, so you can quit, shoot up a bunch of intruding bandits, and resume where you left off.
Dead Ops Arcade 2 (Call of Duty: Black Ops 3)
Platform(s): PS4, Xbox One, PC
Between all the big-budget single-player campaigns, infinite multiplayer matches, and deceptively intricate Zombies modes, the Call of Duty games don't get nearly enough credit for how much raw FPS content they offer up for your enjoyment. Dead Ops Arcade 2 adds even more to the playtime pile in Black Ops 3, hidden away on your Data Vault computer in the campaign. This follow-up to the minigame from the original Black Ops is truly authentic to the '90s arcade aesthetic, with its pixel-art intro cutscene, radical border art befitting a Trapper Keeper, and the appropriately ridiculous subtitle "Cyber's Avengening". The top-down shoot-'em-up gameplay is exactly like Smash TV rendered in COD's engine, with powerful weapons dropping incessantly and droves of point-boosting loot to pick up as you clear each area of zombies. But here's a catch you won't find in Smash TV: occasional stints where you dole out the arcade carnage in first-person, which can get surprisingly intense given just how many flesh-starved undead are jam-packed into each level.
Gwent (The Witcher 3)
Platform(s): PS4, Xbox One, PC
Video games have a rich history of card game sidequests (some of which are included later in this list). The 's Gwent is certainly among the best, even without the - good enough to warrant its own spin-off and make the list of our most anticipated . Gwent's a trading card game built around speed and efficiency. You can tailor your deck to fit a certain playstyle. You can fake out your opponent with different tricks and strategies during a match. But the most refreshing thing about Gwent is that it will end - no matter what - in three rounds or less. That limited play time adds gravitas to each card placed on the table. Strategies must be decided upon quickly, and their results are felt almost instantly; a bad call in the first round could easily lead to an early defeat in the second. Unless that first round was a feint - a ploy to lure your opponent into wasting their best cards. Gwent, like all great TCGs, is a game of calculated risks. What's nice is that it doesn't take another 20 minutes to see if your bet paid off.
Voltorb Flip (Pokemon Heart Gold / Soul Silver)
This unassuming casino game hides an interesting mix of Minesweeper and Picross. Just like in Minesweeper, you want to reveal all the panels on the grid that do not contain mines (or, in this case, electro-shocking Voltorbs). Revealing one of those is an instant Game Over - so avoiding the Voltorbs is where the Picross reasoning comes into play. With a bit of mathematical reasoning and a healthy dose of luck, you can deduce which tiles are most likely to contain Voltorbs based on the clues provided and which tiles you've already flipped over. For example, look at the screenshot above. You see the red box in the bottom left-hand corner? The '02' means the numbers in the column add up to two, while the '3' next to angry-face Voltorb means three of the tiles are Voltorbs. Each row and column is labeled like this, and by comparing them all against each other, you can puzzle out where the Voltorbs are hiding. It's basically one big logic puzzle, and clearing a challenging board will make you feel like you've achieved Holmesian levels of deductive reasoning.
Command Board (Kingdom Hearts Birth by Sleep)
Platform(s): PS4, PS3, PSP
Winning at Command Board feels just like winning at Monopoly: while you're swimming in an ocean of cash, your opponents are stuck paddling around the board bleeding money at every turn. It's a good feeling. You earn your fortunes by buying up colored spaces on the board and - stop me if you've heard this before - improving those spaces so that their rent increases. And you better believe that owning all the spaces of an identical color nets you a hefty rent multiplier. The only thing missing is a diminutive old chap with a cane and tophat - but we'll take Square-Enix and Disney characters over Monopoly's Rich Uncle Pennybags any day. A well-executed game of Command Board is really a thing of beauty: when you conquer the board to its fullest, snag the high-traffic sections you want, and exploit those territories for all they're worth, it makes victory taste that much sweeter. To help speed the game along, each player can also spend cards for special abilities - such as rolling three dice instead of one - to tilt the odds in their favor. The only real drawback is the doltish AI, which can only stumble blindly into victory when Lady Luck has completely abandoned you.
Platform(s): PS3, Xbox 360
Anyone who's seen Tangled knows the story of Rapunzel - that light-hearted fable about the little girl who's kidnapped and confined against her will in a tall tower in the middle of a wooded glen, whose captor climbs her hair like a rope because ladders make way too much sense. In , you can enjoy that delightful children's tale as a puzzling arcade cabinet found in Vincent's favorite watering hole, the Stray Sheep bar. The gameplay here mimics the block-based puzzle stages of Catherine's (somehow more bizarre) main story. As the fabled prince smitten by Rapunzel's beautiful voice and physical appearance, you have a limited number of moves to manipulate a series of blocks and scale them to your objective. Every few stages, a new bit of the minigame's narrative is unveiled via a series of rhymes (), eventually uncovering a tale that's almost as gripping as Vincent's own love life.
Tetra Master (Final Fantasy 9)
Platform(s): PS1, PS3 / Vita (via PSOne Classics), PC
When it comes to Final Fantasy minigames, two of the most loved are both grid-based trading card games: Final Fantasy 8's Triple Triad, and FF9's Tetra Master. In both games, the goal is to control as many of the cards on the playing field as possible (think Tic-Tac-Toe, but far more complex) by the time its grid has been filled out. Here's the kicker: you can gain control of the opponent's cards. In Triple Triad, this was super basic: if the card you played had a higher value assigned to it than the opponent's adjacent card, you'd win. But in Tetra Master, each card had its own HP, damage, and defensive stats, and could potentially attack any adjacent cards or diagonal ones. This adds heaps of strategy to the game, allowing for combo attacks that can sweep the entire board at once (thus explaining those seemingly random situations in which your opponent suddenly flips all your cards and wins the game). Compared to Triple Triad, Tetra Master offers a far deeper layer of strategy, even though its intricate systems are woefully ill-explained.
Tin Pin Slammer (The World Ends With You)
The World Ends With You is one of the most memorable JRPGs in the Nintendo DS catalog thanks to its story, neat battle system, carpal tunnel-inducing control scheme, and, of course, Tin Pin Slammer. The goal of this minigame? To slide your pins around the board in an attempt to knock your opponent's pins out of bounds. Basically, it's 1971's Milton Bradley board game , except the DS stylus replaces the plastic guns and little metal pellets. Crossfiiiiiree!Trying to outmaneuver your opponent makes TPS exciting enough on its own, but the addition of "whammies," or special moves, really cranks things up. You can, for instance, summon a giant mallet from out of nowhere, which spins in a circle and sends every pin it makes contact with flying. Of course, that's not to mention the stage variations, which add handicaps to change the rules on-the-fly, or the fact that you can collect hundreds of pins, each with unique stats and properties. And when you finally overcome a particularly grueling match-up, the sense of accomplishment is glorious. You'll get caught up in the Crossfiiiiirrre!
Geometry Wars (Project Gotham Racing 2)
In hindsight, it's pretty wild to think that one of the Xbox 360's first successful downloadables started life as a minigame in Project Gotham Racing 2. Geometry Wars, a twin-stick arcade shooter, can be found within PGR2's in-game garage between races. What began as a neat side attraction eventually became the primary reason for booting the game back up long after we'd scratched our racing itch. Its ruleset is brilliantly simple: controlling a claw-shaped ship, you have to blow up as many enemies as you can before getting destroyed yourself. It wasn't long before bragging about record PGR lap times gave way to bragging about high scores in Geometry Wars. And because of its popularity, it eventually led to the creation of Geometry Wars: Retro Evolved 2 - one of the .