Sector Z (セクターＺ, Sector Z) is a default stage appearing in Super Smash Bros. based on the Star Fox 64 level Sector Z. It is called "Sector Z" because of the red nebula in the background which resembles the letter "Z". This stage did not return in any later game, but a similar stage atop the Great Fox, Corneria, appeared in Super Smash Bros. Melee and later as a returning stage in Super Smash Bros. Brawl, Super Smash Bros. for Nintendo 3DS and Super Smash Bros. Ultimate.
The Great Fox is the only platform on this stage but it has three different terrain levels. The front two-thirds of the ship are the first terrain with the tip of the wing acting as a good vantage point for projectile throwing. The back third of the ship near the engines and the Arwing bay is another terrain with the left wall being a good place to rack damage on another player.
Arwing fighters will occasionally fire at the players, dealing large amounts of damage and knockback. Also, a character standing on a fighter may be KO'd if the fighter flies offscreen to the top or side; however, the Arwings do tend to barrel roll or fly upside down, which essentially pushes the character off. Unlike the Arwing fighters, though, the main guns of the Great Fox do not fire.
Sector Z is the largest stage in Super Smash Bros.
This stage is based on the Sector Z level from Star Fox 64 (Lylat Wars in the PAL region), in which Invader III ships attempted to ambush the Great Fox, Star Fox's mobile headquarters, by firing six Copperhead Missiles at it; however, Star Fox was able to destroy the missiles and drive away the enemy forces. Sector Z also appears as a multiplayer stage in Star Fox 64.
In this stage, the Great Fox acts as the main platform of the stage, and space junk and Copperhead Missiles occasionally fly past in the background. Also in this stage are Arwings, Star Fox's signature aircraft, that occasionally fly above the stage and are based on their appearance in Star Fox 64. They also appear to have one Laser Upgrade as they fire two lasers at once as opposed to the standard one.
The stage is banned throughout almost all rulesets due to the knockback of the lasers disrupting gameplay, and the excessive size of the stage allowing various types of camping and allowing characters to live up to unusually high percentages. The lower area of the stage also allows easy circle camping and wall combos.