The Gun Course is an area in the Port of South Town in Haven City. It appears in Jak II: Renegade and Jak 3, and seems to be one of the more visited areas. It usually houses a new upgrade for the Morph Gun (such as the Peace Maker and Blaster being held here), or ammo for Jak's guns.
 Jak II
In Jak II: Renegade, the Gun Course just appears to be a small building on the outside. There is nothing flashy around it to signal that it is an important area (except for the occasional Zoomer being left there), but there is a small door that serves as the entrance. It resembles the Underport, another area in the Port, in that manner.
Inside the Gun Course is a completely different story however, There are shooting ranges filled with Metal Heads, Haven citizens, and strange robots (possibly a version of the KG Robots). These robots appear to be cardboard, but some are able to shoot back, and some take more than one hit to destroy with any gun except the Peace Maker. It is not known who actually designed the area, but Krew and his partners seem to be the only people that use it during this time.
The first room that is entered is filled with Krimzon Guard Crates that are filled with ammo for the Morph Gun (all four of the guns; Scatter Gun, Blaster, Vulcan Fury, and Peace Maker). The least common type of ammo to appear is the Peace Maker, so the building and room will have to be exited and entered several times in order to fill up the Peace Maker's ammo capacity.
 Jak 3
In Jak 3, the Gun Course still has the exact same outer appearance. It is, however, more noticeable, because the Metal Head War has left the entire city in shambles, making anything still standing actually stand out from everything else. There are also KG Crates in the front of the building this time, instead of resting inside.
The Gun Course's interior section has been changed just a little bit. It no longer has the KG Crates, but it does have a window here that allows Tess to make new guns. She has now taken over the Gun Course, and (possibly) owns it. She tells Jak and Daxter that making guns is her "hobby", so she'll gladly continue it for them to save the world, and for Jak to protect Daxter.
This time, the Gun Course's shooting range is filled with targets like the KG Blast Bot (in a two-dimensional form), as well as Haven Citizens. A Ratchet and Clank-esque gun course can be bought with the Precursor Orbs that are obtained on Jak and Daxter's journey (it will be in the Secrets menu).
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