Star-vader, Dark Zodiac

[ACT](VC): Legion20000 "Star-vader, Astro Reaper" (If your opponent's vanguard is grade 3 or greater, this unit may return four cards from your drop zone into your deck once, search your deck for the specified card, and Legion) [AUTO](VC):[Counter Blast (1)] When this unit Legion, you may pay the cost. If you do, all of your opponent's locked cards cannot be unlocked during his or her next end phase. [ACT](VC):[Choose one card with the same card name as a unit in your (VC) from your hand, and discard it] Choose a rear-guard in your opponent's front row and back row, and lock them. This ability cannot be used for the rest of that turn. (The locked card is turned face down, and cannot do anything. It turns face up at the end of the owner's turn.)