Gibbering Fiend is a uncommon Creature — Devil card from Shadows over Innistrad (SOI), collector number 161. Current market price: $0.32 (foil $0.62), TCGplayer market prices via Scryfall.
When this creature enters, it deals 1 damage to each opponent. Delirium — At the beginning of each opponent's upkeep, if there are four or more card types among cards in your graveyard, this creature deals 1 damage to that player.