The Ambassador of Fear. A Cleric Boss that appears in the Boss Monster: The Next Level.
Doc Scarecrow is a Cleric Boss introduced in Boss Monster: The Next Level. It has 375 XP and its Level Up Ability states:
For the rest of the game, during the Build phase you may discard to choose one Hero in town. That Hero cannot be lured this turn.
Doc Scarecrow's ability aims to hinder an opponent by "scaring" a Hero to prevent them from entering a dungeon, potentially your opponent's dungeon. The player can discard either a Room Card or a Spell Card to activate Doc Scarecrow's Level Up ability. Thus, cards that can allow the player to take cards from the discard pile, or the ability to draw more cards from the Room or Spell Decks during their turns help give the player ammo to use this Boss' ability.
Doc Scarecrow seems to be a cross between three different medieval elements: a plague doctor, the Grim Reaper, and a Nightmare, which wear creatures that were named so because they gave people bad dreams at night. His name, along with his title "Ambassador of Fear" may also be a reference to the Batman villain, Scarecrow, whose main weapon is fear.