Batteryboom Dragon

(This ability is active if you have one or more face up G units in total on your or G zone):When this unit attacks a vanguard, this unit gets +6000 until end of that battle. :At the end of the battle that this unit attacked a vanguard, if it is the first battle of that turn, choose another of your rear-guards in the same column as this unit, and exchange positions with this unit. (The state of the card does not change)