You’ve just loaded into Super Mario Bros. for the first time. You start to run forward across a brick floor when a brown mushroom trots into view. You’re not expecting it, so you smash right into it. It kills you. One life down, but you’ve made a mistake you know not to repeat. This time, you try to jump over it instead. Your hop is a little short, though, so you wind up crashing down on its head. It goes flat as a pancake and disappears. Well, that’s interesting! You keep running, splatting the little guys until you meet a new critter: a turtle with a green shell. Drawing on what you just learned, you hop on it. Rather than going flat, the turtle retreats into its shell. What now? Playing with fire, you bump into it only to send it flying off in front of you, squashing Goombas in the process. You chase after it with glee… until it ricochets off a brick and kills you. Fair play!
Even 35 years later, that sequence of events still encapsulates the joy of a great Nintendo game. A Mario platformer is a test of skill, but it’s more of a research expedition. Every creature or obstacle you meet is a new variable for you to study. Nintendo’s latest Switch 2 game, Yoshi and the Mysterious Book, takes that foundational design philosophy one step further. What if that discovery process was the whole game? No skill, no sweat, no failure: just a laboratory full of creatures ready to be experimented on.
Yoshi and the Mysterious Book puts its entire focus on playful research to create a low-stakes game aimed at Nintendo’s youngest players. It’s a suitably bright and gentle adventure for parents looking to ease their kids into Nintendo games, but one that doesn’t fully find its footing as a new species of puzzle-platformer. The novel, nascent critter-studying play leaves Yoshi’s new adventure feeling like just the first link in a new evolutionary line.
Harmoniously timed to follow The Super Mario Galaxy Movie, Yoshi and the Mysterious Book puts some of the film’s kid-favorite side-characters front and center. The adventure begins when a living encyclopedia named Mr. E lands on Yoshi’s Island, alongside Kamek and Bowser Jr. Mr. E enlists the help of a multicolored Yoshi army to hop into different biomes housed within his pages and research all the plants and animals that live in them. The game is light on story, even by Mario standards. Instead, there’s an obligatory narrative meant to set up the adventure’s delightful storybook aesthetic.
Building on the arts and crafts motif of both the 2015 Wii U game Yoshi’s Woolly World and the 2019 Switch game Yoshi’s Crafted World, the 2D levels in Yoshi and the Mysterious Book are laid out like a picture book you would read to a kid. (You know, the kind that teaches you that the cow goes moo and the bird goes twee-twee.) Everything looks like it was drawn and shaded with colored pencils, especially the backdrops that feel hand-sketched. Even Yoshi himself moves like he’s in a flip book, his flutter jump animated with a few expressive frames like a Hanna-Barbera cartoon. It doesn’t quite reach the illustrated bliss of Super Mario World 2: Yoshi’s Island, but there’s so much detail and personality in the paper-like levels.
More importantly, it makes it very clear who the intended audience here is: very young kids. That’s true of most Nintendo games to varying degrees, but most Nintendo games don’t have you playing “Mary Had a Little Lamb” and “Twinkle Twinkle Little Star” by bouncing off of musical ducks. The Mysterious Book continues Yoshi’s transformation into an ambassador for a new generation of players, and that’s important to remember as you get into its repeatable, challenge-free play.
Each level, which is less a platforming gauntlet and more a contained 2D playground, is centered around a different creature. Yoshi’s job is to study it by interacting with it in as many ways as he can. Swallow it, ground pound it, put it on his back, chuck it at another creature. Each time he makes a discovery, it is penciled onto the level as if it’s a research note written into a field guide. Each new find gives you stars that unlock more biomes, and you complete a level once you figure out one overarching puzzle. As a concept, it’s closer to Scribblenauts than any of Yoshi’s more traditional outings. It’s about toying with critters, finding out all the things they can do, and getting to personally classify them by naming them whatever you want. Consider it Nintendo’s version of an elementary school science class.
Here’s an example of how that plays out moment to moment. On one page, I clicked on a round, pink creature and entered a small level. I walked forward and saw one waddling back and forth. My first instinct was to eat it, because that’s what Yoshi does. Rather than turning into an egg, as some creatures do, it stayed in Yoshi’s puffed-up cheeks. I held down the eat button again and blew the critter back out like a gum bubble. (I named this one Girby, a portmanteau of “gum” and “Kirby.”) Then I tried jumping on one, which splattered the poor guy. Notes scribbled onto the screen to catalog each discovery. As I moved through the level, I learned that jumping on them while over a gummy pit causes them to multiply instead. With a little experimentation, I soon discovered that doing that a bunch of times heated up a gummy pit until it spit out a bigger version of that creature. While I was never told what the ultimate objective is, I eventually stumbled into it when I found an even larger pit and naturally tried to produce an enormous creature out of it.
There’s just so much to learn every time you pop into a level.
That’s not far off from the experience of playing Super Mario Bros.: see a Koopa, figure out its deal. Yoshi and the Mysterious Book takes that experience and recreates it with tons of delightfully designed critters that all have dozens of unique interactions to find through experimentation. There are frogs that blow bubbles you can hop into, clouds that you can ride across a level, a sentient wakeboard that performs tricks off of waves. You can even inherit some of their abilities by tail flipping them onto Yoshi’s back. Grabbing a fisherman allows Yoshi to both reel in fish and snag well-hidden collectible flowers, for instance. These creatures all interact with one another, too. After clearing a level, you’ll occasionally be able to hop into a variation of it that introduces another critter into that ecosystem. There’s just so much to learn every time you pop into a level.
It’s a sound idea for a kid’s game. I’ve talked to a lot of parents who played Kirby and the Forgotten Land with their child, and they’ve all told me the same experience: While the parent tried to rush through a level, the kid kept stopping to marvel at every little background detail. Children sometimes take joy in simple delights that adults don’t even register. Yoshi and the Mysterious Book is built around that. Every detail, even something as simple as log bridges that press down like piano keys when Yoshi runs across them, is designed to give kids a full toy box that rewards their observation skills rather than their platforming ability. (Yoshi can’t die and there are no game overs to worry about.)
As good-natured as that idea is, it’s never quite taken far enough to sustain a full game. Noodling around with critters gets old across 10 biomes, as you’ll end up going through the same motions to interact with many of the creatures you’ll find. Eat, ground pound, chuck, and tail whip. While there’s a good diversity of big-picture puzzles to solve — tossing drill-nosed bees at wooden targets, catching bugs with a living net, coating a big creature in spores — the repetition starts to make discoveries feel mechanical rather than organic over time.
It’s structurally bizarre, too. After completing the six biomes presented to you at the start, the non-story abruptly ends, and you’re whisked away to the end credits. Anticlimactic, but sure. When that’s done, the unfinished adventure continues on where it left off in a new set of biomes (the later ones are the game’s best, including a Super Mario Bros. 3-like world that turns the tiny creatures you’ve seen into giants). You also unlock a system that lets you trade in any flowers you’ve collected for UI elements that you can stick to the screen any way you want. Some are handy, like a bar that shows you your research progress or points you towards a collectible. Others are bizarre, like tools to measure Yoshi’s speed or show his invisible health bar that serves no real purpose, since Yoshi can’t die. It’s a cute feature to play around with, but it doesn’t do much to actually deepen the puzzle hook in the game’s arbitrarily separated second half. They’re just more toys rather than tools.
Part of the problem is that you rarely get a chance to put any of your learnings to good use. The grand puzzle in each level generally has one strict solution involving the current critter. There aren’t many chances to get creative and, say, bring a bubble-blowing frog into a level with a Girby to test an alternate theory. The experimentation is more careful and guided than it appears to be, and it only opens up in a few late-game challenges that tease a more open-ended approach to puzzling similar to The Legend of Zelda: Echoes of Wisdom.
If you’re looking for a more direct comparison, Yoshi and the Mysterious Book skews closer to Princess Peach Showtime! That game, released in 2024 for the Switch, sported a similarly novel discovery concept, with Peach finding outfits that gave her a new set of abilities, but it rarely gave players space to tinker around with their powers and test what they learned. The play in both games is tightly controlled, more like an interactive museum exhibit with lots of guardrails in place. That’s fine considering the intended audience, but it does stop Yoshi’s adventure from finding the full potential of a good puzzle-platforming concept.
My instinct is to say that I hope to see these ideas fully realized in a more traditional Yoshi game, but I’m not sure if that would be the right solution. Turn Yoshi and the Mysterious Book into a proper platformer where you need to use creatures’ powers to solve your way through levels, and you basically have a Kirby game. What makes this unique is how contained it is, even if that’s what holds it back too. It’s as if you’ve been tossed into the whimsical playtesting lab Nintendo uses to poke and prod at every creature it designs for a new game — more of an extension of Super Mario Maker’s creative freedom than Super Mario Bros. Wonder’s meticulously designed platforming. If anything, a sequel could stand to drop the level-based structure entirely in favor of a true sandbox full of critters to be experimented on. The idea never fully hatches, but I can appreciate the playful concept it’s flutter-jumping towards with great effort. It doesn’t capture that timeless joy of experiencing World 1-1 for the first time, but it at least helps you understand how Nintendo engineers those magical moments.
Yoshi and the Mysterious Book will be released May 21 on Nintendo Switch 2. The game was reviewed on Nintendo Switch 2 using a prerelease download code provided by Nintendo. You can find additional information about Polygon’s ethics policy here.
