Spark Dolls

Spark Dolls (スパークドール) are the transformed bodies of Ultras, monsters and Aliens from various universes.

New Ultraman Retsuden
Ultraman Ginga some time prior to the series, a multiversal war named the Dark Spark War raged between the side of good and the side of evil side, with the participants being comprised of the Ultramen versus the monsters and aliens for the universe. In the middle of the battle a dark giant appeared, looming over everyone else and transformed them into Spark Dolls. It was then that an Ultraman named Ginga fought the dark figure however their battle ended in a draw, resulting in both being changed into Spark Dolls locked away in their respective devices. The devices and the Spark Dolls fell to Earth where the Ginga Spark was eventually found and housed in the Ginga Shrine as a holy object.Years later, Hikaru Raido found the Ginga Spark and the presence of this object caused the various Spark Dolls hidden around his hometown to being to activate. In response the Villain's lackey Alien Valky began going about giving Dark Dummy Spark to corrupt minded individuals to sow chaos on earth.

Ultraman Ginga S
The spar dollls appeared again in the second season of Ultraman Ginga. Their appears to be the Alien Chibu known as Exceller. It is also noted that the Victorium Crystal appearantly have a similar energy signature to that of Spark Dolls.

List of known Spark Dolls in Ultraman Ginga: These have been confirmed to have been in the Dark Spark War List of some of the known Spark Dolls exclusively in Ultraman Ginga: Theater Special Ultra Monster ☆ Hero Battle Royal!: List of known Spark Dolls in Ultraman Ginga S: The origin of  these dolls is unknown.
 * Ultraman Taro
 * Ultraman Ginga
 * Black King
 * Thunder Darambia
 * Kemur Man
 * King Pandon
 * Ragon
 * Doragoris
 * Ultraman Tiga
 * Alien Valky
 * Eleking
 * Jean-nine
 * Red King
 * Barabas
 * Seagoras
 * Bemstar
 * Hanzagiran
 * King Crab
 * Alien Icarus
 * Super Grand King
 * Dark Zagi
 * Alien Nackle
 * Dark Galberos
 * Zaragas
 * Antlar
 * Jashrin
 * Ultraman
 * Ultraseven
 * King Joe
 * Salamandora
 * Gavadon A
 * Gavadon B
 * Aboras
 * Banila
 * Alien Baltan
 * Jirass
 * Gabora
 * Gesura
 * Pigmon
 * Magular
 * Greenmons
 * Gyango
 * Woo
 * Alien Guts
 * Alien Baltan
 * Saigo
 * Kanegon
 * Sartan
 * Beacon
 * Aribunta
 * Alien Hipporito
 * Lunatyx
 * Yapool
 * Jumbo King
 * Alien Temperor
 * Zetton
 * Geronimon
 * Alien Metron
 * Dada
 * Zoa Muruchi
 * Zamusha
 * Miclas
 * Snowgon
 * Telesdon
 * Dorako
 * Kanegon
 * Mochiron
 * Alien Akumania
 * Alien Miracle
 * Gomora
 * Reyonic Burst Gomora
 * EX Gomora
 * Mecha Gomora
 * Yametaranese
 * Alien Empera
 * Hoe
 * Alien Zarab
 * Gango
 * Seabozu
 * Alien Godola
 * Keronia
 * Father of Ultra
 * Zoffy
 * Ultraman Leo
 * Ultraman Mebius
 * EX Red King
 * Eleking
 * Imperializer
 * King Joe Custom
 * Sadora
 * Gudon
 * Vakishim
 * Giant Yapool
 * Gomora
 * Fire Golza
 * Melba
 * Super C.O.V
 * Reigubas
 * Gan Q

Trivia

 * The Spark Dolls are similar to the Ranger Keys of ' and the Rider Cards in '.
 * They are similar to the in that they hold the powers of the beings they resemble. Only in this case they are the beings they represent.
 * They are similar to the, specifically in the movie , in which they both were acquired when they defeat an opponent.
 * Another similarity with the Rider Cards is that they both have their own monster variations
 * They are also similar to the Rider Cards of Kamen Rider Diend whom can summon holographic manifestations of riders.
 * The only known conscious Spark Doll appeared to be Ultraman Taro, however, Ginga spoke in Episode 6, revealing that he too, was still conscious, which was why Hikaru cannot transform at will. Despite speaking in Spark Doll Theater, all of Hikaru's Spark Dolls have had their consciousness sealed (Spark Doll Theater is a comedy show and not canon).
 * They are the first transformation items to have a major toyline, as they replace the Ultra Monster Series and Ultra Hero Series.