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Marks & Brands of Cthulhu (Quirks)

This mod adds a collection of 30 quasi-prismatic, cthulhu-themed quirks targetted for the end game that will require significant investment, time and focus to fully obtain for your intended roster of heroes.

It extends the prismatic quirk system introduced in CoM with a few darker twists. These new quirks have been carefully introduced with an eye for balance and are unlikely to have much of any impact in the early / mid game. (more information below)

Additionally, the player is free to engage as much (or as little) as they wish with the Marks/Brands. Player choice, after all, is always important.

Finally, no vanilla files were replaced or edited. This mod is strictly plug & play.


Cthulhu's Mark is a negative quirk that has the same rate to show up as any other negative quirk. It will weaken the afflicted hero by increasing the damage they take by 15% when below 50% hp.

On its own, the Mark is a bane, but if you can pair the Mark with one of the corresponding God's Brands from the Cthulhu mythos, the hero will receive a tremendous boon.


All Cthulhu Brands are prismatic quirks that offer a significant bonus to the hero only if Cthulhu's Mark is present. Otherwise they do nothing.

The bonuses, when unlocked, are on par, slightly weaker or marginally better than the prismatic variants.

Brands show up at a rate of 0.20% versus vanilla's 1%.

They are very rare, and are the only quirks beyond the player's ability to control unless you micromanage your roster carefully.


Brands of Cthulhu are incompatible with prismatic quirks. This prevents / reduces power creep.

You can however, have multiple Brands on a single hero. The effects of the Brands & Marks will stack with Corvid's as well as vanilla quirks.

Be careful not to underestimate Cthulhu's Mark. 15% more damage taken at 50% hp will often be enough to put your hero at Death's Door.

Is power, insidious as it is, worth the risk? That is for you to decide.


Mods that extend the quirk system will obviously make it statistically impossible to get the correct Brands.

The mod technically makes the game slightly harder as the Brands do not give any bonuses on their own while Cthulhu's Mark will put your heroes at risk of dying.


O'Nightmare: His steam guide on the game's parameters was infinitely valuable. You can find it here: https://steamhost.cn/steamcommunity_com/sharedfiles/filedetails/?id=1095670238

Clair de Lune: For her Discord channel which you can find here: https://discord.gg/VkXB87M
And also because I finally understood how to do up tooltips for rules and buffs by looking at her work in her Trinket Collection.


Want more end game diversity to increase difficulty / rewards at your own control and leisure? Check out: https://steamhost.cn/steamcommunity_com/sharedfiles/filedetails/?id=1447699854

Want significant improvements to vanilla enemy compositions while respecting vanilla's mechanics? You can find it here: https://steamhost.cn/steamcommunity_com/sharedfiles/filedetails/?id=1429179072

Want a marathon campaign setting with increased maintenance costs? Find it here: https://steamhost.cn/steamcommunity_com/sharedfiles/filedetails/?id=1438310168