封魔鉱 フェルン is a Weiß Schwarz card from 葬送のフリーレン Vol.2 SFN/S136-085. Compare listings from Singapore Weiß Schwarz sellers on CardJio, then jio them on WhatsApp.
【AUTO】 When a CX with a Book Trigger is placed in your CX Area, look at the top card of your deck, and put it on top or bottom of your deck, and this turn, this gains the following ability, "【AUTO】 When this card's battle opponent is Reversed, reveal the top card of your deck. If that card is level 1 or higher, add it to hand." 【AUTO】 When this attacks, if you have 2 or more CXes with a Book Trigger in your Waiting Room, this turn, this gets +3000 power.
This card was printed in Japanese only; the English text above is an unofficial community translation.