Geist

"He's disrupting his trion stability on purpose and funneling trion to his weapon and his legs. The way he's treating his weapon as a body part and transforming himself is similar to our approach to Trigger technology in Aftokrator."

- Hyrein analysing Geist's Blade Shift

is a prototype Optional Trigger exclusive to Tamakoma Branch. It is Kyōsuke Karasuma's personal Trigger.

Appearance
When Geist is activated, the contours of the user's trion body start to flicker. A countdown timer and pentagonal appear on the back of the hand corresponding to the chip's location in the user's Trigger holder, which is the left hand for Karasuma. The spider chart has five variables, indicated by the same number of Kanji: in clockwise order from the top,, , , ,and. The values of each parameter range from 1 to 5, and the shape of the diagram changes to reflect the "Shift" in use.

During Blade Shift, the user's legs and dominant arm turn black, swollen and cracked, as if they were encased in rock. A short spike appears on each knuckle of the dominant hand. The transformation spreads to the Attacker Trigger in use, causing vein-like motifs to appear on the base of the blade and the handle, which becomes dark in color. Speed Shifts affects only the user's legs. The mutation they undergo is similar to the one from Blade Shift, but their girth does not increase. Spikes sprout from the user's knees, as well as a join that connects the calf to the heel. Gunner Shift modifies the user's dominant arm and legs up to the knees the same way as Blade Shift. The user's firearm increases in size exponentially, covering their arm from the elbow down. The firearm sports a shield with Old Border's logo on the front and an oblong one on the side opposite the user's body.

Changing shifts undoes the physical modifications.

Overview
Like the other Tamakoma-exclusive Triggers, Geist was developed from technology Takumi Rindō brought back from the Neighborhood. It is currently considered a prototype not approved by Border's HQ. According to Hyrein, this concept of treating one's weapon as a body part and transforming oneself bears similarities to Aftokrator's approach to Trigger technology.

Abilities
Geist enables the user to temporarily enhance their combat capabilities through the use of various "Shifts". More specifically, activating Geist purposely destabilizes the user's trion body, allowing them to funnel the newly destabilized trion into their Triggers and/or specific parts of their trion body, depending on the Shift in use.

The five Shifts focus on a different aspect of combat, redistributing trion in order to increase the user's combat effectiveness in that particular area. This is achieved by disrupting the balance of the trion body, as evidenced by the spider chart: before the first Shift is activated, each parameter has a value of 3, for a total of 15; then, they are modified by each Shift. The user can change Shifts at a moment's notice, but they are unable to deactivate Geist. Their flexibility allows Karasuma to adapt his fighting style in response to the progress of battle.

Users
The only user of this Trigger is Kyōsuke Karasuma.

Trivia

 * "" is a German word that can be translated as "mind", "spirit", or "ghost", depending on the context.
 * When Karasuma enters Blade Shift, the anime incorrectly depicts the value for "Special" as 2 instead of 1.