Initially part of the Cthulhu Wars: Onslaught 3 Kickstarter, the miniature is also available independently with rules on the publisher website.
How to obtain the Eidolon Loyalty Card: Pay 2 Doom to take this Loyalty Card. Then place the Eidolon anywhere on the Map.
Powers:
Hierarchy (Ongoing): The Eidolon generates 1 Power during the Gather Power Phase. He can be Captured like any Cultist and is Recruited, rather than Summoned. He cannot Create or Control Gates.
Eldritch Wisdom (Ongoing): If the Eidolon is in play, after any player's Action you can force each player to write down his or her next Action and then flip this Loyalty Card face-down. Example: an enemy who plans to Move must write "Move" but he need not say which Units are Moving, nor to where. On each player's next Action, they must perform that Action unless it is now impossible to do so. In this case another Action may be taken. Flip this Loyalty Card faceup in the next Doom Phase.