Unlike every other Custom Robo title in the series, the Custom Robo battles in Custom Robo GX are in 2D, instead of 3D, due to the Game Boy Advance not being powerful enough to completely emulate other Custom Robo titles. Also, in its storyline, players can't move the protagonist the same way they can in any other title of the series. In this title, the main character the players name is used as the cursor on the map screen for selecting which place to enter. When the players are inside a place, a pop-up window will give the players choices on what to do inside the place the players are in. The main object of the whole game is to finish its plot by collecting every Custom Robo, battle part, and other stuff that the player wants, while winning every battle that moves the players from one part of the storyline to the next. In Custom Robo battles, the object is to reduce the hit points of the players' opponent from 1000 to 0 by using different Custom Robos, guns, bombs, pods, and Action-Chips. The exclusive Action-Chip within this version allows the players to create an additional shield of defense or to expand on the players' various maneuvers. It is confirmed in this game that many upon many of combinations are present when it comes to the players' specific weapon. This combinational process however is strengthened even greater with the new Action-Chip ability. Battles begin with the players' robo being launched out of a Robocannon which is controlled with the D-pad. Unlike other Custom Robo titles, once shot out of the Robocannon, players have a random amount of time for their Custom Robo to be ready to battle, instead of depending on which six sides of the cube they land on. Custom Robos are arranged in groups that are similar to their abilities. In camera views, unlike other Custom Robo titles, this one has only one, which zooms out whenever two Custom Robos are far from each other, while it zooms in whenever they are close to each other. The endurance bar is located above the players' hit points. Once it runs out, the players' robo gets "downed" which means that it stays fallen for a couple seconds. After it gets up, it goes into "rebirth", where it stays invincible for about 3 seconds. If the player repeatedly loses the same battle, the game offers the option of reducing the opponent's initial health, to make it easier. If the players continue to lose several times, the degree of handicap offered increases up to 75%, giving the opponent a starting 250 HP.
