At Kmart, get a mobile coupon good for 25% off a Nintendo 3DS game by texting "GAME" to "73277". When you receive a text in return, reply with "GAME1", then touch the red "Click for offer" and skip the personalization to get to the actual coupon. That's the best straight percent-off discount we've seen on Nintendo 3DS games from Kmart this year. You'll need to show the coupon on your phone to an in-store cashier in order to use it. Deal ends October 21.
A best bet is to head to a Kmart store and buy Pokemon Y for Nintendo 3DS for $39.99 before the above coupon, $29.99 after. That's the lowest price we could find by $9.