In All-Star mode in Super Smash Bros. Melee, this stage is played on when the player face off against Ness and any of his teammates. In Super Smash Bros. Brawl, Ness is fought here when being unlocked.
The center of the stage is occupied by a building with two awnings which act as soft platforms. Stepping on the awnings makes the sign tilt, and stepping on them two more times makes them drop and become unavailable; they get automatically restored after a short time.
On the right there is a light blue house with a festoon, which acts as a soft platform, over it. On the left there is a yellow house: the tree over it provides two soft platforms which react to the weight of fighters and items.
Several more buildings appear, but, as they're beyond the lateral blast lines, they can't be acessed during gameplay. There is also no lower blast line.
At times a warning sign appears near the side of the screen, signifying that a car or van will pass by the bottom of the stage. The vehicles can hit and damage fighters, as well as destroy or activate items like crates. Every vehicle deals 30% damage, but their other properties differ:
- The Taxi Cab (Yellow car) and Teal Coupe deal exactly the same amount of damage and knockback. The coupe is most likely to spin out whenever it hits an opponent, and the larger the opponent, the more likely.
- The Magenta Coupe deals reverse knockback, meaning that it sends the victim flying behind it, like a much more poweful version of Dr. Mario's down tilt.
- The Runaway Five's Tour Bus spikes any character it hits. Thus, since it's on the ground, it sends donwards airborne fighters in the middle of a short hop and sends upwards grouded fighters. The spike is so powerful, it is capable of star KOing any character above 90%.
The background features several more elements: a hospital, a hotel, a backhoe, and a hill with some houses (including Ness's) and a meteorite on top. On the foreground, outside the normal camera view, there are a white canopy and some bicycles. On the right of the stage, slightly beyond the blast line, there is a sign with a warning about the black van.
Changes from Melee to Brawl
Eagleland: Onett returns in Super Smash Bros. Brawl as EarthBound: Onett. One change in the stage is that the right edge of the left building's roof can no longer be grabbed. Also, there are slight lips on the both sides of the house on the right. This prevents characters against these walls from jumping to avoid cars. However, the cars in this version of Onett are far weaker and have potentially no KO ability unless very close to the walk-off edges, although hitstun is lethal and can interrupt most attacks.
Another slight change to this stage is that the red cross on the building of the Hospital has been removed. This may be because the American Red Cross, who hold the trademark on the symbol, have enacted a fierce protection of the symbol in recent years resulting in its removal from many games and re-releases of games (for example, the health packs in the Xbox Live Arcade re-release of Doom II have also had the red cross removed and replaced by pills, and the health crates that appeared in the Xbox Live Arcade and PlayStation 3 versions of Worms feature green crosses as opposed to the red crosses in previous games). Alternatively, it could be a reference to its removal in the original EarthBound game.
The warning sign on the right side of the stage is only readable in Brawl when the Devil assist trophy moves the stage to the right. The meteor is also not visible without the Devil.
This stage is from EarthBound. In EarthBound, Onett is Ness's hometown in Eagleland and where the story of the game begins. One of the first things the player has to do in EarthBound is go to the drugstore to buy a weapon upgrade. Onett also features red and blue houses. In Melee, the red building on left doesn't look similar to any buildings in EarthBound, but the blue one on the right looks similar to the smaller blue houses in Onett. Ironically, in EarthBound, if one jumps in front of a moving car, it stops until one gets out of the way. This is not true in Melee, as cars continue to drive and even hit the players which might be a reference to either the Car and Van enemies in the Mother series or the Runaway Five's driving, who at one point back the van over the sidewalk and yell, "Hey, sidewalk! Get out of my way!" Vehicles from EarthBound such as the Runaway Five's Tour Bus and taxis are some of the vehicles featured on the stage. Numerous features of Onett and other towns can be seen in the background such as the arcade, bulletin boards, the meteor site and Dusty Dunes Desert. The foreground also features many items from Earthbound, such as the stalls from Burglin Park and bicycles.  The primary music for this stage is from the Mother theme "Bein' Friends", which is the second overworld theme from Mother. The song is also mixed in with Mother's Eight Melodies, and at the end of the song can be heard the tune that plays when the player encounters an enemy in Mother. The alternate music is "Pollyanna", which is the first overworld theme from Mother and the theme that plays shortly for Ness' house in EarthBound. 
- If the player stands just to the right of the blue house and pauses, zoom out to see the "Onett Message Board" to the right. It reads "Caution, A black van driven by this guy (seen in the picture right of the message) has been spotted driving recklessly through town. Be careful!". This sign cannot be properly read in Brawl.
- The meteorite, Lier X. Agerate's, Ness's house, the Minch house, the Traveling Entertainers' Shack and entrance to Giant's Step, the Gold-Digging Man's Backhoe, and the hospital from EarthBound can all be seen in the background. However, the stage's geography differs drastically from that of the original game, as many buildings are incorrectly placed.
- In Super Smash Bros. Brawl, there is a glitch involving the soccer ball item. If the ball is hit and lands on one of the bushes suspended in the air above the left house, it will bounce continuously, causing the bush to bounce, until a player or another item steps onto it.
- Also in Brawl, when Jigglypuff uses Puff Up on the part between two buildings, anyone who stay with Jigglypuff will get stuck and take extreme damage so no one will be unable to go offscreen, until the Final Smash is finished.
- Interestingly, in Brawl whilst other returning stages feature music tracks from another non-returning Melee stage of the same series (Princess Peach's Castle is featured on Rainbow Cruise and Mute City on Big Blue for example), the music from Fourside does not feature on Onett, probably because Onett had an alternate song in Melee (Mother 2). However Pokémon Stadium in Brawl does have 2 alternate songs.
- Since Fourside and New Pork City are also banned from tournaments, that means no stage from the EarthBound/Mother universe has regularly been seen in competitive play.
- In Brawl, if the Onett stage is hacked to where the flowers are removed from in front of the Drug Store, there will be an onigiri (rice ball) behind them. This can be seen in both Melee and Brawl, and it is currently unknown if it is in Super Smash Bros. for Wii U.
- The hospital in the background is placed in a way that, when KO'd characters go flying into the background, they often go flying towards the hospital. This could be a deliberate joke played by the developers.
- Onett is the first Melee stage to be return Super Smash Bros for Wii U.
- In Super Smash Bros. for Wii U, if the player is using a fighter with a counter ability, it can instantly KO their opponent if they use counter against a passing car, from the middle of the field, at 0%. An example is Marth, using counter against a passing car. If the opponent gets hit, and runs into Marth's strike, they'll be launched far enough to get KO'd. The car inflicts 30% damage, which is high enough damage to KO an opponent. However, there are some fighters that can't hit their opponent by using this same combo up close to the opponent. Shulk is an example, since he has a big delay to execute the counter move. In order to actually KO someone as Shulk, they have to be a little farther away from him, so he can hit them (like around the edges of the Drug Store). Some fighters are unable to KO their opponent at 0% at all, such as Lucario and Palutena (Even though she can knock the opponent back far enough, it still can't KO them at 0%).