Speiraskia

The Speiraskia is a Black Trigger used by Mira.

Appearance
Upon activation it takes the appearance of a black circle, not unlike the wormholes it generates, with an outer rim of a lighter color. It hovers above the user's palm. When the user is about to run out of trion, the circle will break down, giving off dark sparks. However, it is still possible to use the Trigger by generating a smaller circle.

Background
Its origins are yet to be known.

Plot
It was used by Mira to sneak into Mikado city from Aftokrator's ship without being detected. She also uses it to send trion soldiers into the city from their ship. After Yoneya defeated Lamvanein, she used it to retrieve him and attempt to hit Yoneya in a surprise attack. Later, she killed Enedra to retrieve his Black Trigger by impaling him with the spikes.

Abilities
It is capable of creating black circles in the sky. These circles can be used as portals connected to where Mira is, or transformed into spikes, to attack enemies. She can also teleport targets away with the portals.

Its weakness seems to be that anyone can use the portals to travel, including enemies, and that the portals will also transport attacks, such as trion bullets. If not carefully monitored, the user runs a risk of an enemy taking advantage of the portals' interconnected characteristic. It is also revealed that this trigger consumes a lot of trion.

Trivia

 * Speiraskia is a combination of the Greek words speira (σπείρα speíra, spiral) and skia (σκια skia, shadow) which means "spiralling shadow".
 * According to the author, Speiraskia is such a strategically useful Trigger that had Aftokrator's goal been to invade Earth, the latter planet would not have stood a chance.