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 over it, which acts as a soft platform. 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 because they are beyond the lateral blast lines, they cannot be accessed 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 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 is 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.
Onett returns in Super Smash Bros. Brawl with multiple changes. The stage prefix is now 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 deal highly reduced knockback, lacking KO ability at realistic percentages unless very close to the walk off edges, although their damage output has not been decreased and they can still disrupt gameplay. Another slight change to this stage is that the red cross on the building of the Hospital has been removed, most likely due to issues about the Red Cross emblem.
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 or when an unrestricted camera hack is in use. In Melee, it can be read simply by standing close to it, pausing and moving the camera.
In SSB4, the vehicles lose their unique launching properties.
The Omega version takes place on a much bigger version of the drug store while on the roof.
The stage is banned in all games it appears in. It saw use as a counterpick in the very early metagame of Melee. The reasons for banning are the same across games; the walls allow for infinite combos (this problem is more prevalent in Melee and not at all in Smash 4), and the stage hazards of the cars can disrupt gameplay and easily allow for early kills. The lack of a lower blast line also removes the edge guarding component of characters; the low ceiling at the top of the stage and the walk-off blast lines also can allow for very easy and early KOs.
Onett is Ness's hometown in EarthBound, though its actual layout is different from this stage's version.
Drug Stores, which unlike in this stage feature only two floors, act as item shops, as well as places where Ness can withdraw and deposit money with an ATM and save the game with a payphone.
The blue house on the right bears resemblance to how small houses were designed in EarthBound, while the yellow house on the left is not designed off any house in the game.
Cars, including Taxis, drive along the streets in the cities, but unlike in this stage they stop when in front of Ness until he gets out of the way. The black van, which in EarthBound never appears in Onett, belongs to the Runaway Five, a band with debts that Ness and his friends help repay. To show their gratitude, they offer Ness a ride from Twoson to Threed. The bulletin board which warns players about the van is inspired by similar bulletin boards in EarthBound which feature miscellaneous messages.
Some of the buildings in the background and outside the stage's bounds are the Onett arcade, where Ness defeats the Sharks and their leader Frank Fly, a Hospital, where in EarthBound status aliments including unconsciousness can be healed, a Hotel, where the party's HP and PP can be fully recovered. The backhoe could be a reference to the one in Dusty Dunes Desert. The canopy in the stage foreground could refer to the similar-looking shops of Burglin Park in Twoson, where a bicycle shop is also located.
The very back of the stage depicts the steep cliffs at the north of Onett. These feature Ness's house, Porky's house, the entrance to the cave which leads to Giant Step and the meteorite which crashes on the top of the hill at the beginning of EarthBound, kickstarting the plot. However, their positioning is different with respect to the source game.
Ω Mode, which takes place on top of a wider version of the drug store featuring some flowers and a trash can, is likely a reference to the first meeting between Ninten and Lloyd in Mother, when Lloyd is hiding in a trash can on the roof of Twinkle Elementary School.