I know how to get the trio but I think it is wrong so I decided to ask you guys
Genies:tornadus/thundurus any route after encounter on route 7.landorus you need thundurus and tornadus.
musketeers:battle cobalion in mistralon cave,then virizion is in pinwheel forest,and terrakion is in victory road
Horse trioor virizion cobalion and terrakion can be found by going to mistralton cave and batlling cobalion then virizion is in pinwheel forest then terrakion is in victory road
Well you can only catch tornadus in black and thunderus in white and having both of these are required to get landorus. Heres the link that will explain in detail. http://www.serebii.net/blackwhite/legendary.shtml