[AUTO]:When this unit is placed on (RC), if you have a grade 3 or greater vanguard with "Masques" in its card name, [COST][Soul-Blast 1], and this unit gets [Power] +5000 until end of turn. If you [Soul-Blast] "Masque of Hydragrum" for this cost, choose one of your opponent's rear-guards, and retire it.