Clone

A clone is a character with a moveset and physics that are considerably similar to another character's. Often, the clone's moveset will have a few tweaks made, and may have their physics altered to a degree, but on the whole the characters are similar and typically have the same special move mechanics, to such a degree that both characters can be played successfully using a very similar or even identical play style.

Clones are a common inclusion in various fighting games, as for a developer it saves a good deal of time to copy a character's moveset and then tweak it than to generate a new one; on the other hand, many fans consider the inclusion of clones to be lazy or uninspired.

A semi-clone is a term used as a sort of midway point being "clone" and "non-clone". Semi-clones share some of their moveset with another character, and may have some similarity in physics, but have enough unique about them that calling them a "clone" wouldn't be entirely accurate. Different players have different opinions of how unique a character has to be to move from "clone" to "semi-clone" status: newer players tend to exaggerate the importance of special moves for character comparison, for example.

The process of decloning a character between iterations of a franchise is often known in the Smash community as Luigification, named after Luigi's origin as a palette swap of Mario to becoming his own unique character in the Mario series, and the fact that Luigi started as a full clone of Mario in the original Smash Bros., but has been decloned in each additional installment.

Clones in Super Smash Bros.

Original	Clone	Differences
Mario	Luigi	Luigi's dash attack is a unique move. All three of his special moves have slight differences: Luigi Cyclone launches foes instead of sucking them in, Luigi's Fireballs are immune to gravity, and the Super Jump Punch either does massive damage or almost none. His taunt is also different. Overall, Luigi is faster but weaker than Mario.
Semi-clones
Kirby	Jigglypuff	Both share similar forward smashes, down smashes, neutral aerials, forward aerials (Kirby's hits multiple times, but he extends both legs in front of him as does Jigglypuff), down aerials, tilts, back throws, item animations, and ledge animations. Both also have near identical physics, with similar size, shape, weight, falling speed, and both possess five midair jumps. Their special moves, however, are all completely different.

Notes

• The Fighting Polygon Team is composed of complete clones, sans special moves, of all 12 playable fighters.
• Samus and Captain Falcon share neutral aerials, down smashes, forward and up tilts, and dash attacks, but have enough unique moves of their own, along with vastly different physics, to not be classified as semi-clones.
• Mario, Luigi, and Ness, interestingly, all share a polygon form, a neutral attack, a forward tilt and a floor recovery attack.

Clones in Super Smash Bros. Melee

Originally, Sakurai was going to include significantly fewer playable characters in Melee. However, with fans wanting more characters while time was constrictive, Sakurai decided to add clones later in development to pad out the roster with characters that would take less time to develop than unique characters. Melee directly identifies its clones by placing them in recessed boxes on the character selection screen, next to the original character.

Original	Clone	Differences
Mario	Dr. Mario	While all attacks have identical animations, many of them have different properties, such as with Dr. Mario, the removal of the forward smash's sourspot while dealing electrical damage, a sex kick that gets stronger over time, and a forward aerial that doesn't meteor smash. Dr. Mario's attacks are also a bit stronger in general. Note that they also share identical physics with the exact same size, shape, weight, and falling speed (though interestingly Dr. Mario has faster air speed).
Link	Young Link	Like the Mario/Dr. Mario pair, while all animations are essentially identical, some attacks act differently. Young Link's forward smash has weak, set knockback on the first hit and only combos into the second hit, while his arrows are on fire and his Spin Attack is a multi-hit move when grounded. Young Link also has some slightly differing physics (faster running speed and higher jumping height), and is generally a faster character with weaker attacks.
Fox	Falco	All attacks have near identical animations and functions, though many have had their knockback altered, changing which ones are good for KOing, such as Falco's forward smash and down tilt being considerably stronger than Fox's, while Fox's up smash and up aerial are considerably stronger. Falco's special moves have identical mechanics but have changed enough that they have different applications; for example his Blaster shots flinch and his Reflector produces vertical knockback instead of semi-spike trajectory horizontal knockback. Falco also runs slower and jumps higher than Fox, while being slightly heavier, and has a down aerial that hits only once.
Pikachu	Pichu	Pichu's up smash is a headbutt instead of a tail flip, its down smash emits no electricity while only hitting once, and its forward smash is a multi-hitting attack. Their special moves, while identical in name and animation, have some differences, as Pichu's Skull Bash can be charged longer and gain more power, Thunder is a multi-hitting attack, and Agility travels further than Quick Attack, while not having hitboxes and being slower. Pichu also damages itself for every electrical attack it uses.
Captain Falcon	Ganondorf	While most attacks have near identical animations, many of them are carried out slower for Ganondorf, with many having altered functioning, and most if not all have elevated power. Ganondorf's forward air and neutral attacks are unique, and Ganondorf's up tilt is radically altered to a point where it can be considered unique, where Ganondorf "charges" with his leg up while smoke is generated, before crashing it down in a large and extremely powerful explosion. Additionally, Ganondorf's dash attack hits in a vertical trajectory behind him while Falcon's hits forward, Ganondorf's forward smash hits vertically while Falcon's hit horizontally (this also applies to their down smash), each kick of Ganondorf's up smash is individually powerful while the kicks in Falcon's are designed to hit into each other (this also applies to their neutral aerial and the inverse applies to their down smash), Ganondorf's back aerial is strong throughout while Falcon's functions like a sex kick, aerial Raptor Boost meteor smashes airborne opponents while aerial Gerudo Dragon doesn't, and aerial Wizard's Foot spikes airborne opponents while aerial Falcon Kick doesn't. Ganondorf's physics are also much different from Falcon's, with Falcon having space animal physics. This is the only clone pair where both characters do not come from the same universe.
Marth	Roy	As Roy's sweetspot is at the hilt of his sword instead of the tip as with Marth's, even attacks that appear to be unchanged in animation and function (that is, almost all of them) must be used differently. Non-sweetspot differences include Blazer being a multi-hit move with set knockback, Counter having a multiplier for determining the strength of the counter strike (as well as a different counterstrike animation), Roy's jab consisting of one hit only, Roy's down tilt hitting opponents vertically instead of semi-spiking, and Roy's up smash being a multi-hitting move. Roy's physics, while similar to Marth's, also have some differences, such as Roy falling faster with a shorter jump, while Marth has less traction. This is the only clone pair where both the original and the clone are unlockable characters.
Semi-clones
Mario	Luigi	Luigi's many changes from Smash 64 to Melee have distanced him from Mario considerably. In addition to his previous differences, he now has a unique forward smash, up tilt, neutral combo, forward aerial, and side special; his other specials have also been further tweaked, such as the Super Jump Punch going straight up and no longer giving horizontal distance. Additionally, Luigi's down smash and neutral aerial have been altered to hit vertically while Mario's hit horizontally, and Luigi's down aerial consists of one strong hit (that can also meteor smash), while Mario's is a multi-hitting attack.

Notes

• In the transition from Super Smash Bros. to Melee, characters like Jigglypuff and Captain Falcon have been differentiated with new attacks. In Jigglypuff's case, it has kept some of its moves from Smash 64, while Kirby has received new ones.
• As Luigi and Dr. Mario share a "parent" in Mario, it stands to reason that the two are semi-clones of each other in some way. This kind of relationship is generally not considered in the definition of "semi-clone", however.
• Interestingly, all head sprites of a clone will face the opposite direction of that of their original characters.
• Samus, Captain Falcon, and Ganondorf all share floor recovery attacks, and have dash attacks that are shoulder blocks and up tilts that are some form of axe kick.
• Bowser and Giga Bowser are clones, having identical movesets, although most of Giga Bowser's moves have some sort of additional effect along with altered knockback.
• The Male and Female Wire Frames are clones of Captain Falcon and Zelda, respectively. They lack special moves, however.
• Master Hand and Crazy Hand can be considered clones, as they share most of their attacks.

Clones in Super Smash Bros. Brawl

While there is considerable grey area on the subject, it can be said that Brawl contains no true clones; rather, it only contains semi-clones - and even this can be disputed at length.

Original	Semi-clone	Differences
Mario	Luigi	The main new difference is Mario Tornado changing from Mario's down special to his down aerial, which makes two more of their attacks completely non-cloned. For some additional new differences, Luigi's up smash has a clear sweetspot and sourspot hitbox while Mario's is the same strength throughout, Luigi has a slight tweak in animation of his neutral aerial, and Luigi's up aerial hits vertically while Mario's hits horizontally. Other previous similarities/differences not addressed still apply in Brawl. For an aesthetic change, Luigi has for the first time been given his own voice, instead of Mario's sped up voice samples. Luigi's general animations have also been differed from Mario's (most notably his helpless animation).
Link	Toon Link	One of the more disputed pairs, as some players believe they have enough similarities to be considered clones rather than semi-clones. Toon Link's unique attacks include his up smash, neutral aerial, forward aerial, back aerial, forward throw, and back throw, while his down aerial is a stall-then-fall that meteor smashes, and his forward smash functioning like a multi-hit smash, despite both having similar animations to Link's counterparts. Other moves of theirs have function differences: Toon Link's down tilt hits horizontally while Link's hits vertically and meteor smashes, Toon Link's dash attack semi-spikes and trips while Link's hits vertically, and Toon Link's down smash functions as a multi-hit attack while each slash in Link's is individually powerful. On the other hand, Toon Link's special moves are based on Link's, though his arrows and Boomerang have different aesthetics and functioning (Toon Link's arrows travel much more slowly while hitting vertically, which also applies to Toon Link's Boomerang and additionally doesn't have the tornado effect of Link's boomerang). Toon Link's grounded Spin Attack functions identically to Young Link's in Melee, though the aerial Spin Attack's hitboxes are almost exactly identical to Link's. For an additional oddity, Toon Link's forward throw wasn't programmed properly (Toon Link's forward throw is considered a Leg attack like Link's even though it's obviously a shoulder tackle). However, they are completely different in their physics and other statistics, such as size, shape, weight, and walking/dashing/falling/air speed.
Fox	Falco	Falco now has a different dashing animation, neutral combo, up tilt, forward smash, neutral aerial, forward aerial, and up aerial, while Fox was given a different back aerial. Both Fox's and Falco's down throws were altered, where Fox's hits opponents far away diagonally, while Falco's hits opponents not far away horizontally. Falco was also given a new down special, where he uses Reflector differently (he kicks it forward where it hits weakly horizontally and can trip, instead of holding it). Additionally, Falco's physics were altered, where he falls slower with faster air speed and less gravity in comparison to Fox (though their physics are still similar). Other similarities and differences that existed in Melee not addressed here still apply in Brawl.
Captain Falcon	Ganondorf	Ganondorf's forward tilt, down tilt, up smash, up throw, and side special are now unique, along with other attacks receiving an alteration in animation, such as Ganondorf's dashing animation, up tilt, down smash, neutral aerial, down aerial, Warlock Punch, Dark Dive, and Wizard's Foot. Ganondorf now also has different animations for general things such as dashing. However, other standard attacks, such as forward smash, up aerial, forward throw, back throw, and down throw, are near identical in animation/function, and their special moves outside their forward special are identical or near identical in function. Other differences they had in Melee not addressed here still exist in Brawl.
Ness	Lucas	Lucas' standard attacks are unique with the exception of his down tilt, forward smash, and up aerial (while they have some alteration to their animation, they are identical in function to Ness'). Their special moves however, are very similar in name and appearance, while having similar mechanics but differing functioning. PK Freeze freezes opponents instead of being a very powerful vertical KO move like PK Flash. Lucas' PK Fire differs to the point where it can be argued to not be cloned, as it's a single hit projectile that knocks opponents away, while Ness' hits multiple times and traps opponents (additionally, Lucas fires his PK Fire with a different animation, and Ness can fire his down diagonally in the air). Lucas' PK Thunder can go through opponents while Ness' can't, and his PK Thunder 2 is a multi-hitting move, while Ness' hits once. However, while the similarity in their moveset can be argued to not be quite enough to label them as semi-clones, they have very similar physics, with them having identical size, shape, weight, and falling speed. They additionally both suffer from 10 additional frames of lag when being grab released that no other characters in Brawl suffer from.

Notes

• The Alloys are all clones (sans special moves): Red Alloy of Captain Falcon, Blue Alloy of Zelda, Yellow Alloy of Mario, and Green Alloy of Kirby.
• Even Master Hand and Crazy Hand have each been Luigified, with Master Hand now having unique moves (his hand swipe, walking hand, and finger missiles attacks), and separate functions in his attacks.
• Many players tend to assume Fox and Wolf are semi-clones, or even full clones, due to their special moves and Final Smash being similar in name and mostly identical in operation. However, closer inspection of their full movesets shows that even calling them semi-clones is difficult to rationalize, as the characters' physics are radically different, none of their standard attacks are similar, and even their similarly named special moves have different particle effects and function differently.
  • In a similar fashion, a few such players assume Marth and Ike to be clones or semi-clones as well, due to them both being swordsmen, having similar appearances, hailing from the same universe, and having a mostly identical down special move in Counter, as well as having neutral special moves that both involve charging up to unleash a strong blow. However, Counter is the only move that these characters truly share (and even that has different animations), and the two have different animations for every single one of their other moves, along with radically different physics.

Clones in Super Smash Bros. 4

Original	Clone	Differences
Marth	Lucina	Marth and Lucina share many moves and general animations, but unlike Marth, every part of Lucina's sword will deal the same damage, instead of being more powerful at the tip, and Lucina is also slightly shorter. The complete extent of her clone status is unknown as of now, however.
Semi-clones
Mario	Luigi	Luigi has a new down throw, where he throws opponents onto the ground and forcibly sits on them. He also has a new jumping animation that differs from Mario, now being his scuttle jump. Differences in Brawl still apply, though no other new differences between the two that will be in the final release are currently known, however.
Link	Toon Link	Link now has a new dash attack, now being his jump slash, and his up aerial has an altered animation, while Toon Link's Spin Attack now produces green attack trails. Differences in Brawl still apply, though no other new differences between the two that will be in the final release are currently known, however.

Cross-generation

Original	Semi-clone	Notes
Young Link	Toon Link	Both younger Links share very similar set of differences with Link - they're smaller, faster, have less reach in their attacks, swords which make "smacking" sounds instead of "slashing" sounds for most of their attacks, and both have more controllable Boomerangs and multi-hitting Spin Attacks, while having a forward smash that is identical in function (both being true multi-hitting attacks). It is commonly assumed by players that Toon Link is essentially Young Link with a different coat of paint, in the same way that Link's design was changed between Melee and Brawl, with the differences between them (such as leg-based aerials being changed to sword attacks) being attributable to a decloning process rather than attempting to make a new Link variation from scratch.