2 Clash of Clans account on the same Game Center account
Attach your old village to a new Game Center account:

Launch Game Center on your old device, create a new free account and login; while logged in, launch the game. If you get the "Welcome back, yourusername" message at the top of the screen, your village is now attached to your Game Center account!

Load your village on the new device:

Launch Game Center on your new device, and login with the same username and password you used in the old device; while logged in, launch the game, and you will get the following message:

Tap "Okay" to load your old village on the new device.  This will delete the new, unwanted village.