"I am mankind's next generation. Mankind can only survive by following me."
- ―Keigo Masaki (as Evil Tiga) speaking through Psytech Building.
Evil Tiga (イーヴィルティガ Īviru Tiga) is an Ancient Giant of Light that bore a strong similarity to Ultraman Tiga. Originally a good Ultra, he became a rampant after being awakened in the present day via a forced merger. Although having been destroyed after his reawakening in the modern times, his remains were collected by TPC in order to create the artificial Ultraman Terranoid in 2017.
The time of the Ultras on Earth had long since ended and only Ultraman Tiga, with the help of the human known as Daigo, was able to appear in the modern age. What remained of this giant race had returned home leaving replicas of themselves in the form of stone statues, but soon a twisted mind would revive one of these ancient warriors.
After his creation Geozark discovered the location of one of the last statues, Dr. Keigo Masaki of the Psytech Corporation stole Daigo’s Spark Lens to unleash the power of this new being. Masaaki fused with the warrior and what resulted was not a force of good. Twisted and warped by a forced merger with Masaki, the giant became Evil Tiga and began to attack humanity. GUTS, knowing this was not their hero, fought back to no avail, but another would rise up to face it when Daigo couldn't: Guarde, the hero’s former companion. The friendly Kaiju did its best to try and calm and stop his old friend, but Evil Tiga was blinded and attacked the creature with blow after blow. As the villain prepared to kill the creature, Daigo managed to recover the Spark Lens and turned into Ultraman Tiga. However upon arrival Masaki made Evil Tiga kill Guarde for no other reason than sadistic pleasure angering Daigo and signaling their battle.
The forces of good and evil clashed in the streets as the two traded attacks, each countering the other. Soon both Ultras hit each other with an energy attack; Tiga's Zepellion Ray and Evil's Evil Shot, which were equally strong, the explosion from the clashing beams knocked both Ultras on their backs. However, as the battle raged on Evil Tiga proved to be slightly faster and more agile than Tiga. Soon the energy of both Tigas began to run low and the two made a last lounge at each other. Evil Tiga went for a jump kick while his light counterpart used sweeping slash. When they landed Tiga grabbed his side in pain from Evil Tiga's blow, all seemed lost until Tiga's blow across Evil Tiga's neck came into effect. The dark giant fell to he ground paralyzed, but eventually got up to his knees. As the evil Ultra was about to charge and fire his final Evil Shot, Tiga acted faster by sending the villain a modified Zepellion Ray. The beam of energy fired engulfed Evil Tiga, purifying him and reverting back into Keigo Masaki.
Evil Tiga reappears in Ultraman Dyna as a member of the Phantom Monster Army, an army consisting of illusions of the monsters that previously appeared. Evil Tiga was an hallucination experienced by the Super GUTS Members and the last to appear before morphing into the true form: Moravia. It was also revealed that sometime after the original Evil Tiga's destruction, TPC initiated Plan F in secret, inspired by Keigo's action and eventually created the artificial Ultraman Terranoid.
Ultraman Ginga Theater Special: Ultra Monster ☆ Hero Battle Royale!
A digital copy of Evil Tiga appeared in Ultraman Ginga Theater Special: Ultra Monster ☆ Hero Battle Royale! as Evil Tiga (Bug Ray) (イーヴィルティガ（バグレー） Īviru Tiga (Bagurē)).
While Hikaru Raido and his friends transformed into Ultras to see who was the strongest via the Livepad, suddenly the virtual world created imitations of five evil/fake Ultras consisted of Chaos Ultraman, Chaosroid T, Evil Tiga, Chaosroid S, and Chaosroid U. The teens in their Ultra forms fought the evil Ultras until they were exhausted. Hikaru/Ginga told them to stand up as they fired their respective finishers at their counterparts. The evil Ultras were killed in the end.
- Height: 54 m
- Weight: 44,000 t
- Time Limit: Evil Tiga also has a time limit, however his Evil Timer went off at a much later time than usual. This could imply that he can last longer on Earth than the real Tiga or that his time limit is based on the damage he has taken.
- Evil Crystal (イーヴィルクリスタル Īviru Kurisutaru): The crystal on Evil Tiga's forehead, whether it would allow him to Type Change is unknown.
- Evil Eye (イーヴィルアイ Īviru Ai): Evil Tiga's eyes are like any other Ultras but they shine blue and have a black shadow around them.
- Evil Timer (イーヴィルタイマー Īviru Taimā): Evil Tiga's Color Timer, it acts like a normal Color Timer despite the fact his inner light was corrupted.
- Evil Protector (イーヴィルプロテクター Īviru Purotekutā): The yellow and red bands on his chest, they are the sturdiest parts of his body and virtually indestructible against attacks. It can withstand ten thousand tons, shock and beams.
- Evil Body (イーヴィルボディー Īviru Bodī): Evil Tiga's body easily shrugged of the beams from the GUTS fighters. It also shined bright white when he first appeared until Masaki's heart corrupted him.
- Evil Shot (イーヴィルショット Īviru Shotto): Evil Tiga's black "L" style beam, fired in an inverse of Ultraman Tiga's hand movements and positioning for the Zepellion Ray. It is as powerful as the Zepellion Ray.
- Evil Barrier (イーヴィルバリアー Īviru Bariā): Evil Tiga can create a purple energy barrier that can redirect beams in any direction he wants.
- Evil Beam (イーヴィルビーム Īviru Bīmu): Evil Tiga can emit powerful energy blasts from his fists. These can be charged up. This move was named the Evil Slash (イーヴィルスラッシュ Īviru Surasshu) in Ultraman FE3 and is fired immediately to serve as a dark counterpart to Tiga's Hand Slash.
- Evil Kick (イーヴィルキック Īviru Kikku): A flying kick but was countered by Tiga with his Brain Chop. According to the setting, its power is said to destroy a huge building with one kick.
- Evil Punch (イーヴィルパンチ Īviru Panchi): A powerful punch.
- Evil Flight (イーヴィルフライト Īviru Furaito): Evil Tiga can fly through the air at speeds that rival those of Ultraman Tiga.
- Geozark Attack (ゲオザークアタック Geozāku Atakku): Evil Tiga rides on top of Geozark's fin, sliding towards the opponent before he delivers a kick attack. This cannot be considered as a tag-team attack, as Geozark's role is only a supporter and is a part of Evil Tiga (player)'s attack.
- Evil Genocider (イーヴィルジェノサイダー Īviru Jinosaidā): A tag-team attack with Gatanothor. Evil Tiga jumps onto Gatanothor's back while the monster exhales Shadow Mist to confuse the opponent. Evil Tiga soon attacks the disoriented opponent until Gatanothor launched the Petrifaction Ray to freeze them. Finally, Evil Tiga absorb the Gatanothor's Shadow Mist to empower his own Evil Shot towards the petrified opponent.
Ultraman Fighting Evolution 3
Evil Tiga reappears in Ultraman Fighting Evolution 3 as a playable character. In Ultra Mode, his support character is Geozark. In the game, his Evil Timer ring has changed into a reused Chaos Ultraman's Color Timer rings.
Lost Heroes 2
The 2015 Compati Hero Series features Evil Tiga as an NPC. Since Keigo Masaki was absent, Evil Tiga was portrayed as a brainwashed Ultra who physically abused Guarde and fought the original Tiga to a standstill. Instead of being defeated, he returned to his senses and supported the players, to the point of taking over Keigo Masaki's role in reviving the petrified Tiga from his defeat by Gatanothor.
- The actions committed by Evil Tiga were as a result of his forced merger with Keigo Masaki, neither in control of Evil Tiga's body. Despite this, Evil Tiga marked the first time a true Ultra was ever evil and the first time Ultras fought each other.
- Chronologically, Evil Tiga is the second Evil Ultra as he was not evil in the past. The first one was Ultraman Tiga, who in the past, as Dark Tiga, was purely evil. Evil Tiga only becomes evil because of his host's evil heart.
- This concept would eventually be inverted for Tiga's backstory in the movie Ultraman Tiga: The Final Odyssey.
- Despite being a giant of light in the series, the energy hue produced from his beam attacks and the fact that he is an affiliate of darkness in most Ultraman stage shows implied that Evil Tiga had slowly shunned his light in favor of darkness, mirroring the incidents that plagued the Ancient Giants of Light.
- Another contributing factor was in the arcade game Mega Monster Battle: ULTRA MONSTERS, where he was shown absorbing Gatanothor's darkness to empower his Evil Shot.
- According to writer Chiaki J. Konaka, Evil Tiga's debut episode, "The One Who Inherits the Shadows", used "Shadows" instead of "Darkness" to indicate that Evil Tiga is a genuine Ultraman and that he was not actually "evil" by natural means.
- Like Ultraman Tiga, Evil Tiga never physically spoke beyond grunts, Masaki had set up a system with a recording of his voice.
- Evil Tiga's original proposal was meant to be a black-colored Ultraman, which was already made in conception by Hiroshi Maruyama since the first airing of Ultraman Neos. His appearance was reworked from a rejected design of Ultraman Tiga.
- Despite his original grunts (provided by Takashi Kora, the actor who also portrayed Keigo Masaki in Ultraman Tiga) was archived, as shown in the Dark Spark set, the game publication Ultraman Fighting Evolution 3 had Evil Tiga's grunts and laughter being provided by Yuji Machi, Ultraman Tiga's first voice actor. In comparison, Yuji's variation is a low-pitch version of the original Tiga's voice.
- Evil Tiga's Evil Timer's sound is a modified and high pitch version of Ultraman Tiga's Color Timer in the original series. However, his Evil Timer's sound in Ultraman Fighting Evolution 3 has changed into a reused Chaos Ultraman's Color Timer sound.
- Evil Tiga is the second Ultra to have blue eyes, the first is Ultraman Powered.
- Evil Tiga is the final enemy in Tiga's storyline of 1998 PS1 video game, Ultraman Tiga & Ultraman Dyna: New Generations.
- It is unknown if Evil Tiga is still alive within Keigo Masaki when he disappeared his Color Timer was still going. However, Masaki showed no evidence of having a transformation item from their merger, implying he does not have the ability to transform into Evil Tiga.
- Evil Tiga survived on Earth for a much longer time than Tiga, fighting GUTS, Guarde and then Tiga before his Color Timer started to blink. It is unknown if this was from a lack of strain during his previous battles, a result of his forced merger with Masaki, his corruption or if Evil Tiga just naturally can last longer than most Ultras. Another theory is that because of Masaki's conditioning of his body, he had greater stamina and therefore could last longer in Ultra Form than Daigo.
- He was chronologically the second ancient Ultra to awake in the modern world.
- It is unknown what Evil Tiga's true name is as was never referred to his real name during his appearance, in fact, the word "Evil Tiga" is used for real-life marketing purposes, with him addressed as a "Tiga Impostor" (ティガの偽者 Tiga no Nisemono) by Rena, despite his status as a genuine Ultraman. In the stage show DARKNESS HEELS～THE LIVE～, Evil Tiga expresses genuine disgust when referred to by his nickname, but never actually reveals his true name.
- Evil Tiga is one of the few dark Ultras to fight in the Dark Spark War.
- In an original concept, Evil Tiga was meant to appear in the 2016 movie, Ultraman X The Movie: Here He Comes! Our Ultraman under the suggestion of writer Takao Nakano but was turned down by Kiyotaka Taguchi after finding the plot too similar to the original Evil Tiga.