Tammuz-an, a planet situated within the Outer Rim Territories of the galaxy, is notable for its history. Not long after the conclusion of the Clone Wars, the kingdom of Tammuz-an procured a group of R-22 prototypes. These prototypes were acquired from Kuat Systems Engineering designers for integration into their planetary defense fleet, subsequent to the Galactic Empire's decision to forgo mass production of the vessel. The designation "Spearheads" for the R-22 ships originated from Tammuz-an, owing to their visual similarity to indigenous spears.
The initial appearance of Tammuz-an within the current Star Wars canon occurred within the galactic map included in the 2016 roleplaying game boxed set, Star Wars: The Force Awakens Beginner Game, produced by Fantasy Flight Games. The Star Wars Legends continuity originally featured the planet Tammuz-an in "The Lost Prince," an episode of the television program Star Wars: Droids: The Adventures of R2-D2 and C-3PO, broadcasted in 1985.
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- " Scarif and Other Planets in the Outer Rim " — Star Wars Encyclopedia