Nightmare Incursion
Mana cost
Mana value6TypeSorcery
Color identity
Black
RarityRare
SetEventide (EVE)
ArtistChuck Lukacs
Price€0.67 · foil €4.12 · $1.59
Nightmare Incursion 

Sorcery
Search target player's library for up to X cards, where X is the number of Swamps you control, and exile them. Then that player shuffles.
Legality
CommanderLegalStandardNot legalPioneerNot legalModernLegalLegacyLegalVintageLegalPauperNot legalBrawlNot legalOathbreakerLegalHistoricNot legalTimelessNot legalPenny DreadfulLegal
Rulings
2008-08-01
The cards are exiled face up, so everyone can see what they are. (This is true of every effect that exiles cards, unless the effect specifically says it exiles those cards face down.)