Jirachi, the Mythical Wish Pokémon of Steel/Psychic type, spends a thousand-year slumber encased in a crystalline shell. This hibernation cycle connects intrinsically to the Millennium Comet, which appears for seven days every millennium. The comet's energy sustains Jirachi during sleep and revitalizes its native Forina region. While dormant, Jirachi remains largely inert but instinctively defends itself if threatened without fully awakening.
It awakens only when exposed to the Millennium Comet's energy and upon hearing a pure voice. Emerging from its rock-like shell, Jirachi appears as a small, white humanoid Pokémon with a three-pointed star-shaped head and yellow streamers resembling comet tails extending from its back. A curved seam on its belly conceals a third eye with a cyan pupil, its "true eye." This eye remains closed unless Jirachi actively grants a wish or absorbs energy.
Jirachi possesses wish-granting abilities, though mechanics vary. In its primary cinematic portrayal, it teleports existing items to fulfill wishes, like transporting candy from a festival stall to Max. In other media, such as Pokémon Adventures, it manifests entirely new entities, including artificial Pokémon like a monstrous Kyogre-shaped water creature or a fake Groudon. These creations can become unstable and destructive if fueled by negative intentions. Granting a wish requires opening the third eye, achieved through force or by establishing trust with the wisher. Jirachi grants up to three wishes per awakening cycle, each inscribed on one of the three teardrop-shaped teal tags hanging from its head points.
Jirachi exhibits a playful, childlike demeanor when interacting with humans. It forms deep emotional bonds quickly, especially with those awakening it, like Max. This bond is mutual, with Jirachi communicating telepathically to affirm enduring connections even after returning to slumber. Despite its benevolence, antagonists seeking to exploit its powers for destructive purposes, such as reviving legendary Pokémon, often target Jirachi. Misuse can cause its energy absorption to spiral out of control, requiring intervention.
In Pokémon Adventures, Jirachi awakens atop the Battle Dome. Its powers are depicted as more versatile here, capable of executing attacks like its exclusive move Doom Desire and fulfilling complex requests like depetrifying individuals. The manga reinforces the three-wish limit per awakening cycle.
After seven days of activity, Jirachi reabsorbs any expended energy, often from catastrophic creations like the fake Groudon, and returns to its crystalline state for another millennium of sleep. It departs with assurances of lasting friendship to those it bonded with.