The Arena is one of the few important areas in Spargus City. It is where matches and battles are fought when the King of Spargus orders them to occur. These matches are always done until everyone dies except for one challenger, and if this rule is broken, then the remaining challengers are severely punished (often thrown out of Spargus, into the Wasteland).
 Jak 3
The Arena's outer environment is mainly sand, but there is a Precursor Kiosk outside that can be talked to in order to try and obtain Precursor Orbs. There are also large stairs that are used to reach the entrance to the Arena, a large door with some sort of symbol painted on it to represent death. Most things around the Arena are large, just to show that this is one of the main areas of Spargus, and a good area in its community.
The interior of the environment, however, is not as pretty. It is, however, overwhelming. The stadium's entrance is a double-path hallway that is filled with Krimzon Guard Crates that got there through some unknown reason (those sent to the Wasteland after Damas may have brought them in) that hold ammo for the Morph Gun. It is filled with many different things in the main area, including a pool full of lava, as well as platforms that rise up and down out of the lava. There is a throne for Damas and his accomplice, Pecker to rest on and enjoy watching the matches.
The Arena is home to only one type of enemy, known as a Matter-Former, a special kind of Marauder. They are brought in after they have been captured out in the desert, and are placed in cages that hold them until their matches in the arena. The Marauders have a certain form of Gunstaff that they use in battle. It is in the shape of a blade, and is able to fire gun shots. It can also be used to attack any enemy that stands in their way, and with their personality, they definitely will use it for that purpose.
There is one other enemy who is found in the Arena, but never fought, and that is Sig. He threatens to shoot Jak with his Peace Maker in order to comply with Damas's rules, but he hesitates, then gives up altogether.
Jak and Daxter compete in the Arena very often in the first act of Jak 3. This is because they have just been accepted into Spargus City, and Damas is forcing them to earn their citizenship by obtaining three pieces of a seal that can only be given out by him. One of those seal pieces is earned in a mission outside of the Arena however.
To earn these seal pieces, Jak must complete the events that Damas throws at him in the arena. One of these is a mission where you get the Eco Drops that are found on different platforms that Jak must climb over and under in order to obtain. This is the tutorial mission for the basic movement in the game, meaning it is the very first mission in the game (similar to the Prison Escape mission in Jak II: Renegade.
The other missions are all battles against the Matter-Formers that Damas throws at the team. They are mainly to introduce new Gun mods, or to carry on with the story (an example of this is when Jak sees Sig for the first time in Jak 3). The battles all vary in terms of battlefield and number, but they are relatively similar in most ways.
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