The man, the myth, the legend. Lucas Gilbertson, the voice of Zero in Mega Man: Maverick Hunter X, Mega Man X: Command Mission, and Mega Man X8, returns to voice the red crusader in a new Mega Man X4 redub -- Zero vs. Colonel.
Though perhaps not as popular as a certain other cutscene, Zero's initial confrontation with Colonel remains an important and noteworthy part of the character's story arc. With the addition of Lucas' vocal cords, it's made all the more exciting.
While you're at it, check out Lucas' previous X4 redub here!