You play Halo Reach? Wanna test your skills and try to win 25,000 cR? The Reach Weekly Challenge for the week of 4/2/12 involves a ton of multikills.
The challenge is called "Multiplicative," and you have to earn 200 multikills in multiplayer Matchmaking this week. The prize: 25,000 cR.
That's a ton of multikills, and I'm far to busy with a bunch of different games to attempt it, but let us know how you fare in this challenge. The Waypoint Blog (for everything Halo) gives this advice:
[…] it's a tough one so make sure you start early. Stock up on snacks, drink plenty of fluids, stretch those trigger fingers, and get ready to rack up a lot of multi-kill medals […]
So there you have it. Good hunting.