With an account that is level 4 or higher, head to www.fusionfall.cartoonnetwork.com and use the 'Redeem a code' option. Enter the codes below and confirm - you will then be able to select the character you want to have the nano and play.
You must have an account which is at least level 4 for this to work. Go to the main website www.fusionfall.cartoonnetwork.com . And at the 'Redeem a code' option type in the following codes (without the quotes) and press 'Go'. Then click on the character you want to have the nano and click 'Play'.
Unlocks Alien X Nano: Enter the code 'FFCcreationforge'
Unlocks Finn Nano: Enter the code 'FFCiminmyelement'
Unlocks Rex Nano: Enter the code 'FFCcontrolnanit'
The following helmets become available when you log in at FusionFall.com and select 'Redeem Code' (left-hand menu) of your 'My Account' page and the on-screen instructions. This codes appeared in the March 2009 - April 2009 newsletter.
Unlock Friskerton Bubblehead Helmet: Enter the code ffcforestphantom
Unlock Zak Saturday Bubblehead Helmet: Enter the code ffccryptidhunter