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Gloomhaven JotL Attack Modifier Deck – How does it work?

This post was last updated on February 2nd, 2024

In Gloomhaven Jaws of the Lion (JotL), the attack modifier deck is a very important component of the combat system that determines the final outcome of your attacks.

Each player’s character has their own attack modifier deck that they use to modify the base attacks they perform during the game.

The game uses this deck as an alternative to the most common dice mechanics seen in Dungeons & Dragons and in many other dungeon-crawl board games.


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How does the Attack Modifier deck work?

gloomhaven jaws of the lion attack modifier deck cards on a dark surface

The function of this deck is straightforward: its sole function is to modify the outcome of each of your attacks, for better or worse depending on the number written on the card you randomly pull from the deck.

Starting Deck Composition

At the beginning of the campaign, each character starts with a standard attack modifier deck that consists of 20 cards. These cards include:

  • Six “+0” cards: nothing happens here;
  • Five “+1” cards: add 1 damage to your attack;
  • Five “-1” cards: subtract 1 damage to your attack;
  • One “+2” card: add 2 damages to your attack;
  • One “-2” card: subtract 2 damages to your attack;
  • One “Null” card: the attack does no damage – critical fail if you wish;
  • One “2x” card: the attack’s damage is doubled – critical hit if you wish.

Performing an Attack

When you perform an attack, you first declare which ability you’re using and which enemy you’re attacking.

You then draw a card from your attack modifier deck and apply its effect to the base attack value of the ability you used.

For example, if you have a base attack of 3 and draw a +1 card, the attack’s total damage would be 4.

Shuffling the Deck

Certain cards in the attack modifier deck, specifically the “Null” and “2x” cards, have a shuffle symbol on them.

When one of these cards is drawn, after the attack is resolved, you must shuffle your entire attack modifier deck.

This ensures that the probability of drawing these impactful cards remains consistent throughout the game.

Deck Customization – Perks

As characters level up and complete certain objectives, they may have the opportunity to improve their attack modifier deck by adding new cards or removing less desirable ones.

This customization is a key aspect of character progression and strategy.

Players can add cards with higher positive modifiers, additional special effects, or remove negative modifiers to make their decks more powerful.

Advantage and Disadvantage

Certain game effects can give a character advantage or disadvantage on an attack, and the mechanic is very similar to Dungeons & Dragons.

When you have advantage, you draw two modifier cards and use the better of the two.

Conversely, when you have disadvantage, you draw two modifier cards and use the worse of the two.

Special Conditions

Some attack modifier cards also apply conditions such as Poison, Wound, Immobilize, etc., in addition to modifying the attack’s damage.


Gloomhaven JotL Attack Modifier deck – How to improve it?

gloomhaven jaws of the lion attack modifier deck cards on a dark surface

The attack modifier deck not only influences the damage output of your attacks but also introduces a deeper layer of strategy and character development to the game.

This deck can be improved by Unlocking Perks.

How do you unlock perks?

There are 2 ways:

  • At each level up;
  • When you receive 3 checkmarks, usually gained through battle goals or scenario rewards.

These perks allow you to tailor your character’s attack modifier deck to your play style and character role.

For example, some perks let you add cards that inflict status effects on enemies, while others allow you to remove negative modifier cards from your deck.

Some characters have unique attack modifier cards that can be added to their decks as part of their class-specific perks.
These cards often have powerful effects that can synergize with the character’s abilities.

I’ve written an in-depth strategy guide on perks for each Gloomhaven Jaws of the Lion Character, so don’t forget to keep an eye on the Gloomhaven page of the website.

Peace.