The fifth game in the Custom Robo series, Custom Robo Arena moves the action into the portable realm again with the first entry on the DS. It is the first in the series to be released in PAL territories, and the second in North America.
The story has the player's character joining the Robo Team 'Numero Uno' and the story unfolds as they attempt to win the Robo Cup. Like all the Custom Robo games, except the GBA incarnation, the battles are conducted in 3D, with the player attempting to defeat their opponent, in a Pokémon fashion similar to the previous games. The touch screen is used to clean off the player's Robo after it becomes dirty, as this reduces its efficiency.
In another first it offers 2 player multiplayer over Nintendo Wi-Fi and allows voice chat and utilises the rivals system seen in Metroid Prime: Hunters.