UFO

The Super Mario series uses UFO symbolism frequently, with flying saucers appearing in many games. However, sometimes they appear as easter eggs with no explanation for their presence.

In Super Mario 3D Land, when Binoculars are used in the level known as World 1-3, players can wait to see a greyish UFO hover into view and fly away. The UFO will reappear every 90 seconds if you stay at the binoculars.

In Super Mario Maker, UFOs occasionally appear. While horned UFOs are plainly shown abducting materials in Super Expert 100 Mario Challenge, these are by no means the only ones in the game. Tapping the letter A in "MARIO" on the title screen will extremely rarely cause a red UFO to fly in from the right side of the screen. When the [//supermariomakerbookmark.nintendo.net Super Mario Maker Bookmark] website was live before it's inevitable death, users could wait on a single page to see a UFO appear from the left side of the window, flying across the background to the right.