Perdition Emperor Dragon, Dragonic Overlord the Great

[ACT](VC): Legion20000 "Perdition Dragon, Dragonic Neoflame" (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) & Choose two cards from your hand, and discard them] At the end of the battle that this unit attacked a rear-guard, if this unit is Legion, you may pay the cost. If you do, [Stand] all of your vanguards. This ability cannot be used for the rest of that turn. [AUTO](VC):[Choose one of your rear-guards with the same name as a unit on your (VC), and retire it] When this unit's attack hits, you may pay the cost. If you do, choose one of your opponent's rear-guards, and retire it.