What do you get if you cross Destroy All Humans with Duck Hunt?
Look, never mind "I don't know" - I'm not trying to tell you a joke. This is a serious rhetorical question. The answer is that you get Martian Panic. Look at the pictures, it's obvious.
Martian Panic is a Wii shooter for up to four players. Martians are invading. There is Panic. It's simple. Shoot the green swine in the face with your WiiMote or optional gun-shaped WiiMote cosy. No friends? No problem! Just grab a second WiiMote and get all John Woo on their scaly martian asses in Dual Wield mode.