"Woman... I like you.."
- ―Gorothunder's first words
Subtitle: Thunderstroke Monster (雷撃獣神 Raigeki Jū-shin)
- Height: 55 m
- Weight: 40,000 t
- Origin: Space
Gorothunder was considered a god of lightning, who controlled lightning throughout the universe. It is said that all who see him will meet their end. He was summoned to Earth by Ultraman Tregear to wreak havoc on humanity.
Gorothunder descended in a storm cloud near Kana Sasaki and Hiroyuki Kudo. He took interest in the former and captured her in his belly button piercing prison before growing to giant size. Hiroyuki was unsure of what to do since fighting him would endanger Kana, but Ultraman Taiga convinced him that they cannot save kana if they do not take action. Hiroyuki transforms into Taiga to fight Gorothunder, but quickly changed to Ultraman Titas after getting knocked down. He used the Electro Buster, but it was overpowered by Gorothunder's beam, and he was then knocked down by Gorothunder using his club. Kana awakened and cheered Titas on, before he fired the Astro Beam at Gorothunder to knock him away. Titas changed back to Taiga and transformed into Tri-Strium.
Using the Taiga Tri Blade, Taiga narrowly slashes off Gorothunder's belly button prison, setting Kana free. He then uses the Titas Burning Hammer to finish off Gorothunder, who used his own beams in a futile effort to attack him.
- Suit Actor: Shun Takahashi
- Voice Actor: Takanori Tsujimoto
- Gorothunder seems to be a homage to several monsters of Ultraman Taro, such as Mochiron.
- Gorothunder's motif seems to be based on the Shinto lightning god Raijin, who creates the sound of thunder by beating his drums, which have Tomoe markings on them. He is also said to steal the uncovered belly buttons of young children who go out during a thunderstorm.
Powers and Weapons
- Goro Tatsumaki (ゴロタツマキ Lit. Goro Tornado): Gorothunder can unleash a tornado from its gauntlet, which was used to suck Kana into its belly button prison.
- Thunder Spark (サンダースパーク Sandā Supāku): From the Tomoe symbols on its chest, Gorothunder can generate electricity attacks. These bolts can be fired from his shoulders, as lightning bolts, or his hands, as a fiery electrical beam. Two simultaneous beams are able to overpower Titas's Electro Buster.
- Goron Rod (ゴロン棒 Goron Bō): A club/mace that can generate up to 100 million amps of electric current, and 1 trillion volts electricity.
- Levitation: Gorothunder can levitate in the air unaided.
- Size Change: By beating his chest rapidly, Gorothunder can propel himself into the air with propulsive flatulence and assume a giant size.