I might be missing some, let me know and I am not covering the power ups. During the time of the legal battle, Chaiyo came up with three of their own Ultras: Ultraman Millennium, Dark Ultraman (an evil Ultra), and Ultraman Elite. These were not used for purposes other than stage shows and merchandise.
He first appeared in the final episode of Ultraman (Episode 39, "Farewell, Ultraman"), thus becoming the very second Ultra-Being from the Land of Light in the Nebula M78 to appear on Earth after Ultraman himself. He used the same same type as Ultraman's Beta Capsule. In Episode 39 of Ultraman, Zoffy used it to separate Hayata from Ultraman. He returned in Mebius.
Father of Ultra
He first appeared in the 27th episode of Ultraman Ace. He is the father of Ultraman Taro. His real name Ken was revealed in Mega Monster Battle: Ultra Galaxy Legend The Movie. I already covered Mother of Ultra.
He is considered to be and respected as the "God" or Elder of all Ultra heroes. Despite the name, he is not the king of the Land of Light.
Ultraman Leo's twin brother, not counting Leo's pet monster Ron, are the only two survivors of the Galactic Lion System in constellation L77.
Keigo Masaki/Evil Tiga
A world class top scientist. He is also a descendant of the ancient race, like Daigo, and bears similar DNA.
Unlike Gaia, Agul is completely blue. Takayama Gamu, the human host of Ultraman Gaia, believes that Gaia is here to save Earth and humanity. On the other hand, Fujimiya Hiroya, the human host of Ultraman Agul, believes Agul to be Earth's natural defence mechanism. He is at first more interested in protecting just the planet itself, even at the expense of humanity (hence the occasional clashes with Gaia).
Ultraman Hikari (Ultraman Light)
He was an excellent scientist who belonged to Space Science Technology Bureau. Appeared in Mabius.
Hunter Knight Tsurugi
The true identity of Hunter Knight Tsurugi (Sword the Hunter Knight), sans armour and with Star Marks (Medals of Honor to the Ultra Race) on his chest similar to Zoffy.
Justice is an Ultra from the Ultraman Cosmos movies. He has victorium ray and crusher mode. He can combine with Ultraman Cosmos to form Ultraman Legend.
Ultraman Noa was the project mascot of Noa: Nostalgia, the first stage in the Ultra N Project, an experiment Tsuburaya Productions held in 2004 to reinvent Ultraman for a new generation of fans.
A powerful Ultra who gives the Max Galaxy bracelet weapon to Ultraman Max. He appear to help Max fight Zetton. He looks similar to Ultraman Mebius.
Belial has access to the Giga Battle Nizer , a device similar to those from the Ultra Galaxy series which gives him the power to control one hundred Ultra Monsters which he uses to attack the Land of Light in Nebula M78, the home of all Ultramen. He appears in Mega Monster Battle: Ultra Galaxy Legend The Movie and Ultraman Zero The Movie: Super Deciding Fight! The Belial Galactic Empire.
Appears in Ultraman Nexus.