Blue Deathster, "Heavenly Death Ray" Stelvane

[AUTO]:When this unit is rode upon by a grade 3 card with "Avantgarda" in its card name, if your soul has a "Blue Deathster, Sora Period", search your deck for up to one grade 2 Strategy card, reveal it and put it into your hand, and shuffle your deck. If you did not reveal a card, you may call this card to (RC).