Clone

A clone character is a common inclusion in the Super Smash Bros. series, and many other fighting games as well. It describes two or more characters that have nearly identical movesets with slight variations in the attacks. From the developer's perspective, a given character's model can be used as a base template from which to build another, and it is usually evident which one is the "original" and which is the clone.

Semi-clones

Semi-cloning (sometimes known as Luigification) is when a character shares some moves of another, while still having some variation in terms of moveset or special attacks. The term originated from Luigi, who was originally nearly indistinguishable from Mario, but has slowly been given his own unique characteristics. (This is similar to the development of Luigi throughout the Mario series' development). Many clones from Melee were then given semi-clone qualities before they returned in Brawl (while some did not return). The exact meaning can vary for different people. Some people believe that any character with clone-like traits that has any variation in attacks are semi-clones, while others think that certain characters need more unique attacks to be a semi-clone.

Clones in SSB

• Mario & Luigi
  • The only moves that aren't cloned are the dash attack and Down Tilt.

Non-playable

• The Fighting Polygon Team is composed of clones of all the playable fighters.
• Metal Mario is an exact copy of Mario, but with more weight and flinch resistance.

Clones in SSBM

In each pair, the former is the "original", while the latter is the clone.

• Mario & Dr. Mario
• Fox & Falco
• Pikachu & Pichu (They both have a few unique animations in walking/running and one unique attack for their up smash.)
• Captain Falcon & Ganondorf (Two unique attacks, also only pair of "original and clone" to originate from different universes.)
• Marth & Roy
• Link & Young Link

Non-playable

• Bowser & Giga Bowser
• Captain Falcon/Princess Zelda & Male/Female Wire Frames
• Mewtwo & Mew (Technically speaking, Mewtwo is a literal clone of Mew, but since Mew itself is not playable, this fact is nigh upon irrelevant in the universe of Super Smash Bros.)

Semi-clones

• Mario & Luigi
  • The former clones have been differentiated with separate normal movesets and side specials.

Notable changes to Luigi between SSB and Melee:

• Luigi has a different side special than Mario.
• Different forward and, to a lesser extent, down aerial attacks.
• Different forward Smash Attack.
• Different Up Tilt.
• Different neutral combo.

Clones in SSBB

• Link & Toon Link
  • Only a few somewhat different attacks. Most notably, Toon Link doesn't kick in his aerials, and Link has some attacks that peform more slashes than the same attack of Toon Link's. Toon Link's down aerial is also a Stall-Then-Fall aerial.

Non-playable

• Captain Falcon & Red Alloy
• Princess Zelda & Blue Alloy
• Mario & Yellow Alloy
• Kirby & Green Alloy

Semi-clones/Luigified Characters

Most of the semi-clones have some of the same standard moves as the original, but they may have greatly different animations and hitboxes in attacks, and in movement (walking, jumping, etc.).

• Fox & Falco
  • Reflector works differently, but all other special moves are cloned. Some non-cloned moves include neutral air, forward air, and forward smash, among others. Falco's Back aerial is a sex kick. Also, they share the same Final Smash.
• Captain Falcon & Ganondorf
  • A totally different Final Smash and some different standard attacks, but some normal moves are still similar. And most notably, they both share 3 special moves. (Only difference is that Capt. Falcon has fire in his specials and Ganondorf's specials feature darkness.)
• Mario & Luigi
  • Some of their ground attacks and most aerials are the same. However, two of their specials are different, as well as Final Smashes. Now that they barely share any moves, many smashers don't even consider them to be semi-clones at this point.
• Ness & Lucas
  • Only share 3 special attacks. (Ness has PK Flash & Lucas has PK Freeze). However, PK Freeze & PK Flash still work a little differently. They also have the same Final Smash. A few standard attacks are also somewhat similar, such as forward smash, up aerial, and down tilt. But even considering this, they are barely even "clone" characters at all.
• Fox & Wolf
  • The only moves that seem almost the same are Final Smash and Standard/Down Special moves. Wolf Flash and Fire Wolf may seem to be similar to Fox's moves, but they actually move and hit quite differently, and almost all of Wolf's standard attacks are different from Fox's. These two are on the very edge of "semi-clone" status, even less so than Ness and Lucas.

Notes

These categorizations are not official, and are subject to interpretation. Notable controversies are that some people consider Link and Toon Link to have enough separate attacks to make them semi-clones, and some people believe that Marth and Ike have enough similarities to put them in the semi-clone category.