Reugosite

Reugosite appeared in 2018 TV series called Ultraman R/B. Reugosite (ルーゴサイト Rūgosaito) is the final villain of Ultraman R/B. Originally a benevolent gaseous organism, it was corrupted and became a planet eater which eventually materialized as a draconic Kaiju on Earth.

Reugosite was originally a Space Leukocyte (宇宙の白血球 Uchū no Hakkekkyū) that eradicated the adverse effects of space until a certain mask-wearing blue Ultraman rewrote its genetic information, making it go rogue and destroy countless planets. It approached Urban Planet Nepta (都市惑星ネプタToshi Wakusei Neputa), where the siblings Rosso, Blu and Grigio were expecting it after being called to go there by the Voice of Light of Planet O-50. They planned to use their Gyros to turn Reugosite into a solid form before they can defeat it. However, the conversion process was incomplete and Reugosite was stuck in an intermediate form, causing destruction to the planet. Blu attacked and Rosso and Grigio followed. The brothers manage to freeze Reugosite using a combination of the powers of Water and Wind, but it broke free and returned to its gaseous state. In their battle, Reugosite demonstrated enough power to turn Grigio Regina back into Grigio King and then Bone, and the fight caused a wormhole to be opened, throwing them to the space near Planet Earth. Reugosite intended to absorb Earth's life energy and then destroy it, and then fired a finisher beam at Rosso and Blu, who lost the beam lock but managed to drive Reugosite back. Unfortunately, the three siblings fell down to Earth as the Ayaka Star, and the brothers died, scattering into R/B Crystals.

As Aizen Tech detected that Reugosite would be returning to Earth, Saki planned to turn the planet into a massive bomb in an attempt to destroy the powerful monster. Having returned to Earth in present times, Mio Minato succeeded in imprisoning Reugosite into a R/B Crystal, using equipment from Aizen Tech and the three Gyros. She later wanted to have the R/B Crystal thrown into the dimension she was trapped in for the past 15 years. However, Saki claimed the crystal after taking back her Gyro, closing the portal and stating that Mio's way is not the solution in stopping Reugosite. After Saki defeated Ultraman Ruebe as Grigio Regina, Reugosite's R/B Crystal activated itself, cancelling out her transformation and assuming its Kaiju form via Saki's Gyro.

Reugosite proceeded to destroy everything in its path until Grigio Regina reappeared. Saki tried to stall Reugosite until the Ray Energy gathered at the Aizen Tech premises, while Reugosite withstood all her attacks. Once that happened, a barrier was placed around Aizen Tech to prevent Reugosite from escaping. The Aizen Tech building's Monster Restraint System was also fired at it, but Reugosite shrugged it off and used its tentacles to cut off the part of the tower that fired the beam. Preparing to finish off Grigio Regina, Reugosite fired the Genesis Requiem, which was blocked by Rosso and Blu, who appeared and fired their signature Ultra Beams to counter it. Reugosite fired yet another beam and struck Grigio Regina, who defended the brothers after being reminded of what her they did for her 1300 years ago. Saki died while doing so.

Rosso and Blu then charged in fighting and transformed into Ruebe. During the battle, electrical equipment was damaged and the barrier around Aizen Tech was shut down. Just as Rosso and Blu were about to be finished off by Reugosite, Mio was reminded of what she saw in the other dimension and cut off their transformation by locking her sons' Gyros. The Aizen Tech tower fired another beam that momentarily stunned it. Meanwhile, Mio prepared the final step of her plan, which was to pull the entirety of the Aizen Tech premises along with Reugosite and herself into a giant portal to the other dimension.

After a talk among the Minato family, the brothers transform once more. Rosso, Blu and later on Ruebe fought well, convincing Mio to stop and believe in her sons. Despite that, Ruebe's power was not enough and was almost defeated, until Asahi realized what she truly is and transformed into the Makoto Crystal. With a final beam lock between the Genesis Requiem and the Shin Vortex Buster, Reugosite was finally put to an end.

Gas

 * Genesis Requiem (ゲネシスレクイエム Geneshisu Rekuiemu): A powerful destruction ray.
 * Planetary Destruction: According to Mio, Reugosite destroys planets after covering them with its gaseous body. What happens next is unknown, but Mio describes it with a crushing action, a sort of sudden compression.

Monster

 * R/B Crystal Sentience: Reugosite can break itself free from its imprisonment within the R/B Crystal as well as cancel out Saki's transformation into Grigio Regina.
 * Genesis Requiem (ゲネシスレクイエム Geneshisu Rekuiemu): Reugosite's special attack, a laser beam from his chest that can wipe out any living being. Mio's vision in the other dimension reveals that it can instantly turn Rosso and Blu into statues of ash. The attack can be further charged for a stronger attack, easily piercing through Grigio Regina's tough armored body.
 * Genesis Dirge (ゲネシスダージ Geneshisu Dāji): Reugosite can fire a powerful red laser from its mouth.
 * Reugo-Tentacle (ルーゴテンタクル Rūgo Tentakuru): Reugosite has a spike on each arm, which can be fired at foes on the ends of long, extendable tentacles. They can be used for constricting foes and utilized as powerful whip weapons and when not extended, can be used as blades for melee combat.
 * Reugo-Ballistic (ルーゴバリスティック Rūgo Barisutikku): The spikes on Reugosite's centipede-like tail (Named Stinger Needles (スティンガーニードル Sutinga Nīdoru) can be launched as missiles. Also known as Genesis Rain (ゲネシスレイン Geneshisu Rein).
 * Genesis Seal (ゲネシスシール Geneshisu Shīru): Reugosite manipulates space with wave energy, and creates a protective barrier to block attacks.
 * Energy Pulse: In Ultraman Fusion Fight!, Reugosite can release a burst of white energy from its hand.
 * Flight: Reugosite can fly by enlarging the wings on its back. It can also dematerialize the wings if they are not needed.
 * Durability: Reugosite possess great durability and strength, capable of withstanding physical and energy-based attacks easily without flinching.
 * Combined Assault: Reugosite can simultaneously fire his Genesis Requiem and Reugo-Ballistic for a more powerful attack.