Mega Man X8 (Rockman X8 in Japan) is the eighth and most recent game in the Mega Man X video game series, released in PlayStation 2 and PC. After fan complaints over Mega Man X7's foray into 3-D, Capcom went back to 2-D linear progression through stages, although there are two 3-D rail-shooter stages in the game. Also, an unlockable demo of X8 was featured in the PlayStation 2 version of Mega Man X Command Mission.

It is the year 21XX. X, Axl, and Zero are sent on a mission near the Jakob Tower to investigate a unique crab-like Mechaniloid. They manage to defeat it, but are then interrupted by a hail of missiles from Vile, who has apparently been resurrected from his earlier defeat in Mega Man X3. Vile has kidnapped the Jakob Tower project leader, Lumine, for unknown reasons and it becomes the Maverick Hunters' mission to rescue him.

However, what the Hunters do not know is that Sigma has returned once again, this time with his most ambitious plot yet. In Mega Man X7, it was revealed that Axl is the first of his kind, a prototype next-generation Reploid that has the ability to copy other reploids' DNA via a copy chip. In addition, they have subroutines built in to prevent them from going Maverick.