Blood on the Altar Mythos je třetí Mythos rozšíření z cyklu The Dunwich Legacy pro kooperativní karetní hru Arkham Horror Arkham Horror LCG.

Rozšíření je v angličtině a je k němu zapotřebí vlastnit základní sadu.

"It is hard to prevent the impression of a faint, malign odour about the village street, as of the massed mould and decay of centuries."
-H.P. Lovecraft, The Dunwich Horror

Blood on the Altar is the third Mythos Pack in The Dunwich Legacy cycle for Arkham Horror: The Card Game. Its sixty cards (including a complete playset of each new player card), challenge you to delve the secrets of Dunwich, where you suspect a series of recent disappearances may be related to the events in Arkham. But the more you explore, the more you get the impression the townsfolk aren't exactly pleased to see you. There are secrets in this town that its inhabitants don't wish to share…

Even as your investigation of the town leads you to many of the locations infamously identified in H.P. Lovecraft's classic tale, The Dunwich Horror, the player cards in Blood on the Altar allow you to translate the experience you gained in your previous adventures to Permanent new Talents, several new assets, events, and skill cards, and higher-level, more efficient versions of cards from the Core Set.