Elytra

Elytra (, Elytra) is Steve's up special move in Super Smash Bros. Ultimate.

Overview
When used, Steve hops upward, unfurls his Elytra, and attaches a Firework Rocket on it, propelling him upward. The move functions somewhat like Brawl's glide mechanic and resembles 's Wings of Icarus: aiming the move upward grants the highest vertical recovery, but causes Steve to stall when at the move's apex and enter freefall, in addition to minimal horizontal distance; the move itself is more suited to horizontal recovery. A damaging hitbox is created on startup (as Steve lights the rocket). After the rocket is used up, hitting a wall or ceiling will cause Steve to crash and enter free fall. Dodging or attacking during the glide will cancel Elytra, causing Steve to fall but letting him retain the ability to move side to side.

Triple jump glitch
Prior to version of Ultimate, a glitch existed which allowed Steve to gain a second midair jump (i.e. triple jump) if the move was interrupted by a hitbox at the right time. Specifically, if Steve was hit out of the move on frames 1-7 for the aerial version, or frames 6-12 for the grounded version, he would gain the ability to jump twice in the air. This glitch could be activated deliberately by Steve himself using TNT, and would even work if Steve had used up his midair jump, giving him a further two jumps in the air. Likewise, using spirits with the Additional Midair Jump skill would increase Steve's number of jumps and therefore the number of jumps usable by this glitch, allowing up to four in normal gameplay (five if using the skill from the Skill Tree in World of Light).

While the cause of this glitch is largely unknown, it has been proposed that the glitch functions by causing the game to reset Steve's maximum jump counter, including his grounded jump, which he is allowed to use as a midair jump.

Elytra boosting
Elytra boosting refers to a range of advanced techniques which allow Steve to cover greater distances using his Elytra, improving his recovery. The most common and practical form of Elytra boosting involves quickly flicking downwards immediately after the Elytra's fireworks are launched, and then allowing the left stick to return to a neutral position.

An alternate method of Elytra boosting is to flick the upwards-special input to allow Steve to fly fully horizontally; once the fireworks have run out, begin slowly inputting an extremely light upwards input on the control stick. If successful, Steve will begin arcing upwards and will cover a massive distance, both horizontally and vertically. This method is particularly useful when attempting to recover from the bottom corners of the stage without a jump and materials, or in order to fly under the stage to the other side's ledge.

E.P.I.C.
E.P.I.C. (Elytra push induced cancel), discovered by, refers to an advanced technique which allows Steve to improve his actionability out of an initial dash. Normally, when a character undergoes an initial dash, they are locked out of a wide range of moves until they enter a "run" state. The only moves which can be inputted during the initial dash are jumps, up smashes, dash attacks, dash grabs, pivots, and up specials. Furthermore, if Steve uses his Elytra while directly under a 2-block high block, his Elytra will immediately cancel and leave him fully actionable. As such, Steve can use his initial dash to go under a block, use an up special (Elytra), and immediately use any move that may have been otherwise impossible during initial-dash (such as shield or forward smash). This technique, although somewhat niche, can significantly improve Steve's approaching options. In addition, E.P.I.C. provides an alternate and easier method to achieve a jump-cancelled minecart, done by jumping out of the minecart while under blocks and instantly using up-special (though this does require two adjacent blocks rather than one).

For a more nuanced description of E.P.I.C. and its value, WhyDo has created a dedicated video detailing the technique.

Origin
The elytra is an item in Minecraft introduced in the Java Edition 1.9 update which can be found in treasure rooms on End Ships. It is the only source of flight in Survival game mode. When falling, the elytra can be used by pressing jump and the player will immediately start gliding. Firework rockets can be used to increase the elytra's propulsion, allowing the player to fly for a longer period of time. An unenchanted elytra can be used for 7 minutes and 11 seconds before it stops working, at which point it needs to be repaired with either another elytra or phantom membranes.

The elytra was inspired by the Wing Cap from Super Mario 64 and both have similar gliding mechanics.

In the real world, an (pluralised as elytra) is a hardened forewing on insects that closes over and protect the more delicate hindwings. Elytra can not be used for powered flight but can be used to glide and slow descent.

Trivia

 * This move features the most recent addition to Minecraft represented in Steve's moveset, as the ability to use firework rockets for propulsion with Elytra was added in December 2016.
 * While Elytra's glide has been compared to Brawl's glide mechanic, none of the code is reused from Brawl.
 * Oddly, the move's Dutch name in Ultimate is "Elytra" (which is completely identical to the English name for the move), despite the fact that the term used for elytra in the official Dutch-language version of Minecraft is actually "dekschild".