Thanos

How Thanos joined the Tourney
Thanos was born on Titan, a moon of the planet Saturn to Mentor and Sui-San. Due to a genetic quirk Thanos is born with the Deviant gene and as such resembles the Deviants - the Eternals' cousin race - more than his own people. Although treated fairly by his race, Thanos is mindful of his appearance and becomes distant, only keeping company with his brother Eros. Thanos matures to adulthood, and via the use of bionics and mysticism augments his abilities to easily become the most powerful of the Titanian-born Eternals.

Bitter at being an outsider, Thanos is driven insane and becomes fascinated with nihilism, embarking on his quest to "please" death, and begins by conducting a nuclear bombardment of Titan that kills millions of his race. Many years later, Thanos begins his plan to conquer the galaxy by building a base on Earth and constructing a space vessel in the solar system. It is at this time that Mistress Death - drawn by the level of Thanos' obsession and his now considerable power - manifests itself before Thanos, being an abstract entity and the personification of the universal concept of death. Thanos becomes determined to prove his "love" to Death for this sign of affection by destroying all life in the universe.

After obtaining the Soul Gem from Adam Warlock, Thanos develops a weapon with the other Infinity Gems powerful enough to destroy stars. Thanos is once again defeated and turned into stone. Years later, the Silver Surfer witnesses the resurrection of Thanos by Mistress Death, who feels that Death needs a champion once again. A revived Thanos decides to collect the Infinity Gems, which he takes from the In-Betweener and the Elders of the Universe. Thanos then combines the gems on his left glove to create the Infinity Gauntlet, which allows him to exceed the power he once possessed with the Cosmic Cube. Thanos honors Death by erasing half the population of the universe, and then goes on to defeat the entire cosmic hierarchy (e.g., Galactus, the Celestials, Eternity) as Death watches. A group of Earth's superheroes almost defeat an overconfident Thanos, who then loses the Gauntlet to the space pirate Nebula, who claims to be his granddaughter. Nebula then undoes all of Thanos' changes, only to then lose the Gauntlet shortly after to Adam Warlock.

How to Unlock
The player must complete one of the following requirements to unlock Seong Mi-na: For all of these options, the player must brawl Thanos on the Kyoto Castle stage. After defeating Thanos, the announcer will say "Someone else has joined the Tourney!" after a Smash Ball appears on the lower-right corner of the screen with a message saying "You can now use the extremely strong Thanos. He defeated everyone in the Marvel universe, but will he defeat you? ". You will then see him to the left of Spawn, to the right of Venom, above B.B. Hood, and below Jill on the Character Select Screen.
 * Play 800 matches in the Versus Mode.
 * Using Cervantes, finish Classic Mode.
 * Build a stage in the Super Stage Builder, then brawl on a Custom Stage.

Purification (Neutral)
Thanos creates a large pillar of energy from the ground that covers the full vertical range of the screen.

Titan Crush (Side)
Thanos dashes towards his opponent(s) and attempts to ram them.

Anti-Air Titan Crush (Up)
This is basically the upper version of the Titan Crush.

Death Sphere (Down)
Thanos throws a bubble at his opponent trapping them.

Sphere Flame (Hyper Smash)
Thanos makes a sphere out of the energy his armor produces and shoots it upwards. If it does not directly hit the opponent then it will burst and make spread out smaller shots.

Gauntlet (Final Smash)
First, using the Infinity Gem of Power, Thanos throws an orb of fire at the opponent. Then, using the Infinity Gem of Reality, Thanos creates two walls and smashes them together. Next, using the Infinity Gem of Space, Thanos creates a wormhole and debris fly into it, then another wormhole opens up where the opponent is and the debris falls on them. Finally, using the Infinity Gem of Soul, Thanos hits the opponent with a lightning bolt and drains them of health.

Victory Animations

 * 1) Thanos raises the Infinity Gauntlet with the Infinity Gems glowing as he says "Destiny awaits!".
 * 2) Lady Death hugs Thanos while he smiles at the camera and says "With the Infinity Gems, Thanos reigns!".
 * 3) Thanos stomps the gound in front of himself and swipes his right arm before doing a victory uppercut with his left arm, saying "No one can kill a Titan God like me, NOT EVEN YOU!".

Trivia

 * Thanos shares his English voice actor with Azazel and Night Terror.
 * Thanos borrows some quotes from other Smash Bros. Tourney participants during gameplay, such as "DIE ONE-THOUSAND DEATHS!" on the Character Select Screen.
 * Thanos's On-Screen Appearance SFX was previously featured in Tekken: Blood Vengeance when a wooden wall broke open and Kazuya appeared afterwards. This is also true with Banjo, Captain America, Xianghua, Magneto, and Pyrrha.
 * Thanos's Super Smash Bros. Tourney rival happens to be Count Dracula's daughter, Mavis.
 * Thanos and Doctor Doom were previously bosses in the Capcom arcade game, Marvel Super Heroes, and though Doctor Doom is playable from the beginning, Thanos is not.