Find out how to unlock the secret Light Blue Yoshi character using Mario Tennis Open’s hidden QR Reader, on the Nintendo 3DS!

QR Codes for…
…Yellow Yoshi: http://youtu.be/qRJX0HHIXIc
…Pink Yoshi: http://youtu.be/LEz6Z-QWRz4
…Blue Yoshi? http://youtu.be/MaQNMH90q1E
…the Yoshi Costume: http://youtu.be/7sJBZyC0fpw

Note: These will only work on North American copies.

Source: www.gonintendo.com