Nintendo has usually given 2 big titles for 3DS during the holidays with the exception of 2012.
2011-Super Mario 3D Land+Mario Kart 7
2012-Paper Mario: Sticker Star(Animal Crossing should have been a worldwide release)
2013-Pokemon X/Y+Legend of Zelda: A Link Between Worlds
2014-Super Smash Bros 3DS+Pokémon Omega Ruby/Alpha Sapphire
2015-??????????
So what do u think will be the big holiday titles for 3DS this year? I think we will see Pokemon again, likely an expansion/sequel to X/Y, could be Z or XZ/YZ or X2/Y2. For the second big title, I'm not entirely sure, I don't think it will be a mega seller but rather a nice support title. Maybe a sequel to an already released million seller like Fire Emblem or Mario & Luigi or Kid Icarus. Perhaps a Nintendo franchise that has yet to release on 3DS like 2D Metroid or the rumored Diddy Kong Racing or maybe a completely new ip.
Basically Pokemon along with a mid-size support ip capable of selling 1-2 million is my guess.
When the herd loses its way, the shepard must kill the bull that leads them astray.
