Kaname Kuran

If Kaname is your boss, you must play the Vampire Knight set; start the game with only Yuki in your hand & the rest of the drafted cards face-down in the GY.
If a card in the GY is revealed, use the effect:
{b}: Flip Kaname upside down (can lose game).
{u}: Auto win, add RAIN to opponent's hand.
{r/w}/{u/r}: Play revealed card instead.