The Harmonizer Description: This gun shoots out sound waves. When the enemy gets hit by one, their wiimote goes crazy. It starts emitting loud creepy moans and starts rumbling like crazy. Alt-fire: This an alternate mode. During this mode, the whole screen get's blurry and your vision is terrible. The power increases dramatically though and the sound waves spread farther. In order to take full use of this alt-fire, you'll have to resort to using your other senses to make up for your loss of eyesight. For starters, your hearing increases tenfold, so it is much easier to hear the direction of where someone is. When an enemy is near your crosshair, a beeping sound emits from your wiimote, telling you to unleash a powerful kamehameha blast. It wastes a ton of ammo during this alternate fire though.
ARC-Coop Description: A machine connected to the players back, like a backpack. Connected to the backpack are 4 guns. Whats so unique about this weapon is that each gun is controlled by a separate wiimote, with player one controlling the character. Each gun acts like a minigun, but are terribly weak and slow. To use this weapon to it's greating potential, I'd suggest having 3 other people controlling the weapon with you.
It's times like this that I wish I were more creative.
But I like the sound wave idea. Here's my take on it
Wave Cannon A large, cylindrical cannon that is held like a minigun. The front has what looks like a large speaker on it. It fires a shock wave forward in cone shape that expands as it gets further away. The sound wave can bounce off of objects but the further away from the player, the less damage. Able to fire three waves per second. The target is made temporarily deaf when hit. Alt fire: Shock waves come out of the gun in a circle around the player, allowing you to hit people that are close to you (even behind or above you) without even aiming. The downside is that the range is shorter (only a few feet).
Deadly at short to medium range (even around corners), but less effective at a distance.