The murk of the Wanderbrine concealed unseemly rituals designed to bring out the worst in merrowkind.

New Capenna Commander

Inkfathom Witch

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)
{2}{U}{B}: Each unblocked creature has base power and toughness 4/1 until end of turn.

Planechase Anthology

Planechase 2012

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)
{2}{U}{B}: Each unblocked creature becomes 4/1 until end of turn.

Shadowmoor

Fear
{2}{U}{B}: Each unblocked creature becomes 4/1 until end of turn.