Umbris, Fear Manifest gets +1/+1 for each card your opponents own in exile.
Whenever Umbris or another Nightmare or Horror enters the battlefield under your control, target opponent exiles cards from the top of their library until they exile a land card.
Near Mint - $10.25
Lightly Played - $9.75
Moderately Played - $8.25
Heavily Played - $6.25
Damaged - $5.25
Near Mint Non-English - $10.25
Lightly Played Non-English - $9.75
Moderately Played Non-English - $8.25
Heavily Played Non-English - $6.25
Damaged Non-English - $5.25