Amazon offers Prime members the Skylanders SuperChargers: Drivers Smash Hit Character Pack for $5.85 with free shipping. (Non-members can spend $35 or more to qualify for free shipping; otherwise, shippings costs $4.98.) That's at least $5 less than you'd spend at a local retail store. It requires the SuperChargers Portal to be used in-game.

Also available for Prime members is the Skylanders SuperChargers: Drivers High Volt Character Pack for $6.07 with free shipping. (As above, non-members can spend $35 or more to dodge the $4.98 shipping fee.) That's also at least $5 less than you'd pay at a local store.