Pokemon Jade Version for the Game Boy Color is an unofficial, pirated bootleg of the Japanese game Keitai Denjuu Telefang: Speed Version. It features a heavily broken, often unplayable English translation, focusing on capturing "Denjuu" monsters by phone rather than Pokémon. It is famous for "Shishigami" creature from Princess Mononoke on the boxart. 

Key Characteristics:

• True Identity: It is a heavily modified ROM hack of Keitai Denjuu Telefang 1 (Speed Version).
• Gameplay Mechanism: Instead of Poké Balls, you call monsters on a cell phone to join your team.
• Battle System: Battles feature automatic, fast-paced monster fighting, often with immediate healing between fights.
• Translation: The English translation is notorious for being broken, nonsensical, and largely unplayable, often freezing or providing cryptic messages.
• Box Art: Features a creature resembling the forest spirit from Princess Mononoke, often paired with a fake "Diamond" version.
• Release Context: Released around the time of Pokémon Gold and Silver, many collectors were fooled by the, at the time, convincing packaging.

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