Jak X: Combat Racing (known as simply Jak X in PAL regions) is a 2005 vehicular combat video game developed by Naughty Dog and published by Sony Computer Entertainment for the PlayStation 2 console. It is the fourth installment in the Jak and Daxter series. The plot follows protagonist Jak and his allies who, after having been poisoned, must partake in a championship of the fictional sport of "combat racing" in an effort to obtain an antidote. The gameplay differs from previous installments in the series, focusing on arcade racing rather than action-adventure gameplay. However, the driving mechanics of the game were modeled after the previous entry in the series, Jak 3. Furthermore, Combat Racing was the first Jak and Daxter game to feature a multiplayer mode, with the second being Daxter. In 2017, the game was re-released for the PlayStation 4, alongside Jak and Daxter: The Precursor Legacy, Jak II, and Jak 3, all of which later became available on PlayStation 5 through backwards compatibility.