From CAPCOM:
We are pleased to announce during this week’s Mega Man 10 launch that the rumors are true! Mega Man 10 does indeed have an additional character you can play as, and that character is Bass! On April 5 th, users can download Bass for 200 Wii points.
Dr. Wily designed Bass with Mega Man’s abilities in mind. Of course there’s a bitter rivalry between the two, although Bass will help Mega Man out if he sees a benefit for himself.
Bass uses a weapon called the Bass Buster, which is a lot like the Mega Buster except that it fires faster and can fire upwards and diagonally (7 directions in all). He can also use the Bass Buster to shoot-down enemy attacks! He uses dash to avoid enemy advances. He can also copy the weapons of the bosses in the game after defeating them, just like Mega Man can. When he combines with his robotic canine pal Treble, he can fly and shoot more powerful projectiles with his buster.
About Mega Man 10
Set within the zany Mega Man universe, it comes as no surprise that robotic shenanigans are afoot once again. The year is 20XX and a suspicious outbreak of Roboenza, a Robot Flu, has broken out. It spreads through the world like wildfire bringing down robots everywhere. People who have relied on helpful robots for ages are unnerved trying to live their lives without their robot assistance. But robots that would be aiding in the development of a vaccine can’t do their jobs. One month after the outbreak, the situation worsens even more. Infected robots have gone out of control, destroying the city and holding it hostage! Who is behind this mess? It’s up to Mega Man to take on this sinister threat and get to the bottom of this viral mystery.