- NB: ArkhamDB now incorporates errata from the Arkham Horror FAQ in its card text, so the ArkhamDB text and the card image above differ, as the ArkhamDB text has been edited to contain this erratum (updated August 2022): Erratum: The purchase restriction on this card should be replaced with the keyword: "Researched." - FAQ, v.2.0, August 2022
Item. Relic. Tome.
Exhaust Forbidden Tome: Move 1 damage from a player card at your location to an enemy at your location. Reduce this ability's cost by 1 action for every 4 cards in your hand (to a minimum of ).
As written you can heal your friends with this, since it only specifies that you're moving damage from "a player card at your location". This includes damage on your friends and their assets. Team up with a friend on Beat Cop (2) and start shooting down 2 HP enemies without taking a test, or healing best friend Mark Harrigan so he can draw more cards and boost his skill value further; all while helping kill enemies and not taking any skill tests.
Definitely consider Shrewd Analysis if you're running these books; Secrets Revealed is very good action compression if you can get to 12 cards, but at 8 it's action neutral if you move (which is worth it to avoid taking a test). This one though is up there for one of the best health healing cards in the game because it does something proactive when you do it. Most healing is very reactive and therefore doesn't help you win a scenario if you would not otherwise be defeated.
An hilarious Seeker card, letting you heal and damage for one action, but only in the biggest of Big Hand decks. Harvey likes this, but does anyone else? Maybe Big Hand Mandy or Daisy. Of course, you want to make sure you are taking some damage for this to be useful, and Seekers are notoriously low-Health, so it's a bit of a gamble....