So, in white 2, beat the game, defeated team plasma and elite four, went to where kyurem should be, but he was not there? Suggestions?
You have to catch Reshiram first. After you beat N and he gives you the Light Stone go to the Dragonspiral tower to catch it. after you catch it N will show up and tell you that Kyurem has returned to the Giant Chasm.
You have to beat N first. Follow the Zoroark near the end of Victory Road to find N.