In Japan, the second Famicom controller had a built-in microphone. It wasn't used in many games, but in the Japanese Kid Icarus version, shopkeepers sometimes gave players discount when they talked into it.
Pit appears as a playable character in the Wii game Super Smash Bros.: Brawl.
For the Wii Virtual Console version of "Kid Icarus", the passwords that worked on the original NES version have been removed and disabled.
Kid Icarus' protagonist Pit's latest return as a playable character is in the Nintendo Wii game Super Smash Bros. Brawl (2008).
Whoever translated the Japanese game and manual into English obviously didn't know anything about Greek mythology --- "Parthena" (Greek "Virgin") is written as "Palutena" (page 42), and the serpent "Hydra" is written as "Hewdraw" (page 35). We can be glad they didn't write "Medusa" as "Mehdewsah".
The original Japanese release of Kid Icarus for the Famicom Disk System was titled "Hikari Shinwa: Partena no Kagami", which roughly translates to "Light Mythology: Partena's Mirror".
On page 38 of the U.S. Kid Icarus instruction manual (page 45 of the Japanese manual), the Syren enemy has bare breasts. It is perhaps the first (and only) female Nintendo character to sport breasts with nipples.
The Nintendo DS game Electroplankton includes sound effects and the dungeon theme music from Kid Icarus.
Kid Icarus, like Metroid, features multiple endings. The ending appears to be based on the number of points the player obtains, whereas the Metroid ending varied depending on the amount of time taken to complete the game.
The original Japanese release of Kid Icarus for the Famicom Disk System featured disk-save backup (as Legend of Zelda had). But, like Metroid, the U.S. cartridge release used a password save as opposed to battery backup.
Pit (or Kid Icarus) made his first and regular animated appearance in the Saturday morning TV cartoon "Captain N: The Game Master". The series also featured his enemy, the Eggplant Wizard.
It seems that Samus Aran wasn't the only one who had to face Metroids in her adventures. Called the "Komayto", a floating creature that looks and moves exactly like a Metroid, is described as "A mysterious floating creature. Nobody knows where it came from. One theory has it that it came from a planet other than the Earth. It's a nasty jellyfish monster."
Kid Icarus was voted #83 in the Top 100 Games of All Time poll published by Game Informer Magazine (Issue 100, August 2001).
The name "Icarus" comes from the myth about a boy who made wings out of feathers and wax and flew too close to the sun. "Medusa" was one of the three gorgon sisters whose looks could turn a man to stone. The boss "Pandora" is named after the woman in "Pandora's Box", who opened the box and unleashed all the evils upon mankind. The first boss is a two-headed dog that guards the Underworld Fortress, sort of like the Cerberus that guarded the entrance to Hades. The Syren is named after the sirens that would sing and lure sailors to their doom. The Uranos and Pluton enemies are named after Roman gods, Uranus and Pluto. Finally, Zeus is the main "god" of Greek myth.