Archlord Zerato [DR2-EN146] Ultra Rare Trials of the Kingdom if you control no monsters:

if you control no monsters: You can target 1 "Ancient Gear" monster in your Graveyard

add 1 Spellcaster-Type monster from your Deck to your hand

when your opponent Normal or Special Summons a monster(s): Target 1 of those monsters

Special Summon this card from the GY

remove it from play

Archlord Zerato [DR2-EN146] Ultra Rare Trials of the Kingdom if you control no monsters:Set: Dark Revelation Volume 2 Card type: Effect Monster Rarity: Ultra Rare Attack: 2800 Defense: 2300 This card cannot be Normal Summoned or Set. This card cannot be Special Summoned except by Tributing 1 face up 'Warrior of Zera' on your side of the field while 'The Sanctuary in the Sky' is on the field. If "The Sanctuary in the Sky" is on your side of the field, by discarding 1 LIGHT Monster Card from your hand to the Graveyard, destroy all monsters