Ginga Spark

The Ginga Spark (ギンガスパーク) is the transformation item that is used by Hikaru Raido, the protagonist of the series Ultraman Ginga. It is a legendary Item in the Land of Light, said to be only be accessable to a chosen savior bearing the Mark of Courage. It is said to be the only thing able to break the curse of the Dark Spark.

Ultraman Ginga
The origins of the Ginga Spark are unknown. It was once used by Ultraman Ginga to battle the owner of the Dark Spark. However, Ginga clearly lost and was transformed into a Spark Doll, and the Spark fell to Earth where for centuries it was protected and worshipped at Hikaru Raido's family shrine. One day, when he returned, he found the shrine had been burned down and the Ginga Spark, which was being protected by Hikaru's grandfather. The presence of the Ginga Spark was causing the Spark Dolls hidden all over the village to begin activating.

After Ginga defeated Dark Lugiel and all of the spark dolls were freed from the curse of the Dark Spark, Ginga departed back home with the other Spark Dolls. Although Ginga was supposed to return back to his future universe, his transformation item, the Ginga Spark still in Hikaru's possession, meaning that his bond with Hikaru didn't lose even when he is faraway in the universe, returning if Earth is in danger again.

Ultraman Ginga S
In Ultraman Ginga S, Hikaru is shown using the Ginga Spark again after Ginga reunites with him to fight against Alien Chibu and his armies. He is shown having it on his person despite it not being of any use.

Ultraman Taro later transform himself into the Strium Brace, granting Ultraman Ginga a new form by simply connecting the tip of Ginga Spark and the Strium Brace to transform Ginga into Ultraman Ginga Strium, which enables him to use the power of six Ultra Brothers.

Powers and Abilities
The Ginga Spark is an object of Legend in the Land of Light, presumably it posseses great power. It is known that it is the light counterpart to the  Dark Spark. Only the 'chosen one' signified by the Mark of Courage, can wield it, in anyone else's hands it is useless. The mark appears on this person's hand and is similar to the Live Sign seen on Spark Dolls.
 * UltraLive: By touching the Live sign of a Spark Doll with the tip of the Ginga Spark, the user can transform into that Spark Doll's original form.
 * Ultraman Ginga Spark Doll: The Ultraman Ginga Spark Doll is stored within the Ginga Spark, it appears when the Mark of Courage glows, causing the Spark's handle to open and its face to appear. In Ultraman Ginga S, Hikaru can summon Ginga Spark Doll without the Mark of Courage.
 * Spark Doll Detection: The Ginga Spark can detect Spark Dolls.
 * Ginga Spark Lance : Ginga can transform the Ginga Spark into a triden-like lance. Initially used against Dark Lugiel, in its first appearance, the Ginga Spark Lance was surrounded by white light. In Ultraman Ginga S, the Ginga Spark Lance was used again, with the details now revealed.
 * Ability to repel evil: The Ginga Spark, when touched by a being with strong minus energy, such as an evil alien, it will automatically deliver a shock and repel that being away. It can also see past illusions, such as when Alien Icarus disguised itself as Misuzu and tried to touch it. Despite this, humans with dark hearts seem to have no issue touching the object.
 * Ginga Light Spark: The Ginga Spark, through the Ginga shrine, can materialize a Ginga Light Spark, to those worthy and with justified reasons.

How to use
Hikaru selects a doll, scans the mark on its left foot (or the equivalent) with the device and raises it into the air. It is known that when he uses it on another Spark Doll, the device shouts out "UltraLive" and then the name of the Spark Doll he uses (Does not work on Ultraman Taro). However, when he uses the Ginga Doll, Ultraman Ginga's face will appear on the Ginga Spark before transforming. This might be due to the fact that the Ginga Spark is connected to Ultraman Ginga.

Trivia

 * The Ginga Spark is the first transformation item shown being used before the Ultra's human host acquires it. It is shown being used as a weapon to fight the owner of the Dark Spark and his device.
 * The Ginga Spark will be voiced by the same voice actor as Ultraman Ginga, who also happens to voice Ultraman Taro.
 * The Ginga Spark and the Dark Spark are similar to name to the Plasma Spark. The fact that all three items are objects of great power is most likely not a coincidence. Both Ginga and Darkness Spark are stated to objects of Legend in the Land of Light by Taro
 * The Ginga Spark is similar to the used by Kamen Rider Decade and the  used by Kaizoku Sentai Gokaiger. As they can change the user into another Ultra, Rider or Ranger.
 * This is also the first transformation item that lets a host transform into a monster, like Black King.
 * It is unknown if there is a priest to the Ginga Spark, because then Ultraman Ginga would be the descendent of that priest.