While Bug Catching with their friends, the 11-year old protagonist (Nate if male and Katie if female) discovers an odd-looking gashapon vending machine near a shrine. After inserting a coin, something — or really, someone — comes out of the capsule. The ghost-looking being named Whisper claims to be a Yo-kai. He gives the protagonist a special Yo-kai Watch that can detect Yo-kai. With that, the adventure starts.
A port of the game was released on Nintendo Switch in Japan in October 2019.
This game provides examples of:
- Always Night: The Extreme Dare chapter. Since many stores are closed at night, the summer festival's food stands serve as substitutes.
- Bonus Boss:
- Gargaros the red oni can be fought when Terror Time arrives, though he is very strong and it is not recommended for players to fight him until the epilogue rolls around. Players can fight Ogralus the blue oni after defeating Gargaros, and defeating Ogralus allows players to fight Orcanos the black oni, the strongest of them all.
- Duwheel can be found in the Abandoned Tunnels. However, players need to upgrade their watch to Rank A to access the eastern part of the Tunnels to find the rest of the materials that allow them access to the boss.
- Chirpster can be fought after a lengthy series of sidequests in the Abandoned Mansion, setting up a party for the Yo-kai there.
- The Infinite Inferno contains palette swaps of the story bosses and one unique boss at the bottom: Wobblewok.
- Childhood Marriage Promise: The request "Marry Me Someday?" has you finding a nice ring for a little boy (who appears to be between the ages of 5 and 7) who wants to propose to his "girlfriend." Whisper even lampshades this and wonders if they'll be able to get married when they're older. This gets a Continuity Nod in the second game, where you can see them planning their wedding outside the local preschool.
- Early-Installment Weirdness:
- Yo-Kai Watch is much different in tone compared the second and third games. Much of the humor of the first game is much more reserved compared to the Denser and Wackier sequels. In addition, several important characters have their personalities altered to be more in line with the anime (e.g., Whisper becoming the Know-Nothing Know-It-All in 2 compared to his well-informed self in 1). The second game is when the series began combining with anime canon.
- Until Yo-kai Watch 4 broke tradition, this was the only game not to come in multiple versions, international versions of Yo-kai Watch 3 notwithstanding.
- In the Japanese and Korean versions, the game's opening lacks a theme song, only showing an animated cutscene where Nate uses the Crank-a-kai for the first time. Later main series games (and the western release of the first game) would include an opening theme song.
- The trophy system is much different in this game. From Yo-kai Watch 2 and onward, trophies are an Achievement System where you receive bronze, silver, or gold trophies for completing certain goals. In this game, you get trophies by catching a specific Yo-criminal three times to get it to give you three parts of a password. Entering the password in the Lambert post office will net you the trophy for that specific Yo-criminal.
- This game's Final Boss (McKraken) is the only one in the series to not have some sort of Freudian Excuse for their actions or motivations, just being a fairly generically evil dictator.
- No Fair Cheating: A variant: if you mess with the system clock, Gargaros will show up to give you a stern lecture and that's basically all that happens.note
- Only the Worthy May Pass: In the final area the Yo-kai World, the path to the final boss is blocked by three gates guarded by the Terror Time Oni trio. Out of loyalty to late King Enma, you need to prove yourself worthy to each of them before you can pass through. In this case, your worthiness is determined by whether you've done enough requests for the people of Springdale, your ability to answer a question honestly, and if you've won enough battles.
- Peninsula of Power Leveling: One can gain access to a small section of the abandoned hospital, an A-rank Dungeon, while their watch is still only D-rank by climbing some vines on the western wall to get into a window on the third floor.
- The Seven Mysteries: The "summer festival" section of the game has the characters talk about the Seven Mysteries of their school, and that episode's story is focused on investigating one such mystery.
- She Is Not My Girlfriend: If you're playing as a girl in the museum chapter, Eddie insists that taking you to the museum is NOT a date. Nope. Whisper naturally lampshades this.
- Sneaking Out at Night: The protagonist has to go to the hot springs at night to get Mr. Goodsight's favorite pair of lucky underwear while Baku shapeshifts into them in case their parents come in. Unfortunately, as soon as they sneak out, Terror Time begins and Gargaros is on the warpath.
- Starter Mon: Cadin. Despite Jibanyan being the one-per-game Mascot Mook and the starter in later games, he doesn't appear in this one until chapter 2.
- Thinly-Veiled Dub Country Change: The game originally took place in a normal Japanese city, but this was changed in translations. The English version is set in the USA, and besides westernized names and a currency change, there's almost nothing in the game that feels very American. There are still Japanese shrines in various locations, Japanese food sold at stores, and the environment is overall very Japanese. This almost came back to haunt the series when Yo-kai Watch 3 was revealed to be set in the USA, but the translators instead sent Nate to a Southern state.
- The Very Definitely Final Dungeon: The Yo-Kai World. However, after that, you have to go back into Uptown Springdale to make all of the cherry blossom trees bloom. However, all of the enemies there are scripted.
- Wham Episode: Funnily enough, because the games are broken up into discreet "episodes" rather like a television show, it's very easy for easy-to-identify Wham Episodes to exist. The game has the infiltration of the construction site and the confrontation with Kyubi, kicking off the wider Yo-kai crisis facing Springdale.