Ancient Dragon, Spinodriver

(This ability is active if you have four or more damage):［Choose two of your Tachikaze rear-guards, and retire them] When a Tachikaze rides this unit, you may pay the cost. If you do, draw two cards, choose your vanguard, and that unit gets +10000/ +1 until end of turn. :When this unit attacks, if the number of rear-guards you have is more than your opponent's, this unit gets +2000 until end of that battle. /:Lord (If you have a unit without a same clan as this unit, this unit cannot attack)