Powered by the Apocalypse games take diverse approaches to representing injury, stress, and deteriorating health. Unlike traditional RPGs with their focus on hit points, PbtA harm systems often try for other narrative consequences.

Dungeon World 1e and many of its descendants are an exception: they maintain familiar territory with a hit-point system, though adding tags and debilities to create narrative weight. This approach helps transition traditional players to PbtA. (For a long discussion of the trade-offs, see In Defense of Hit Points.)

Harm Clocks

Harm clockApocalypse World introduced the harm clock, a revolutionary approach that: 

  • Tracks damage from 1-6
  • Creates specific fictional consequences at different levels
  • Triggers moves when harm reaches certain thresholds
  • Integrates with healing and recovery mechanics
  • Forces difficult choices about treating injuries.

The system also has a nice cadence of different types of harm. “Harm before 6:00 heals automatically with time. Harm after 9:00 gets worse with time, unless stabilized. If the player marks the segment 11:00 to 12:00, the character’s life has become untenable.” Untenable doesn’t have to mean dead: they take a penalty to hard, a bonus to weird, change to a new playbook, or die.

While this system influenced many subsequent designs, other PbtA games have developed various approaches: debilities, conditions, and stress.

Debilities

Some games have debilities that hurt relevant stats. In Dungeon World 1e, each debility maps to a unique stat—

Losing HP is a general thing, it’s getting tired, bruised, cut, and so on. Some wounds are deeper though. These are debilities.

Weak (STR): You can’t exert much force. Maybe it’s just fatigue and injury, or maybe your strength was drained by magic.

Shaky (DEX): You’re unsteady on your feet, and you’ve got a shake in your hands.

…

Not every attack inflicts a debility—they’re most often associated with magic, poison, or stranger things like a vampire sucking your blood. Each debility is tied to an ability and gives you -1 to that ability’s modifier…. Debilities are harder to heal than HP.

In Stonetop, this system has been streamlined and changed—

Player characters can suffer up to three different debilities:

  • Weakened: the character is fatigued, tired, sluggish, shaky. They suffer disadvantage when rolling +STR or +DEX.
  • Dazed: the character is out of it, befuddled, not thinking clearly. They suffer disadvantage when rolling +INT or +WIS.
  • Miserable: the character is greatly distressed, grumpy or angry, unwell, in pain. They suffer disadvantage when rolling +CON or +CHA.

In addition to the mechanical penalty, debilities have fictional consequences. A miserable character is miserable, and you should weave that into your descriptions and your GM moves.

Conditions

Games like Masks use conditions (Angry, Afraid, Guilty, Hopeless, Insecure) rather than physical harm, reflecting a focus on emotional and interpersonal conflict. Characters mark conditions when hurt either physically or emotionally, creating a unified system for tracking all types of stress. In Masks, conditions affect specific basic moves; e.g., being Afraid is -2 to Directly Engage a Threat.

In Pasión de las Pasiones, each playbook has its own unique set of conditions, each of which grant a bonus to one move and a penalty to another. The playbook El Jefe has the conditions Lustful, Raging, Reactive, and Righteous (+1 to Demand What You Deserve & -2 to Manipulate a Superior), while La Doña has the conditions Cautious, Chiding, Righteous, and Ruminative (+1 to Process Your Feelings & -2 to Express Your Love).

Games with conditions often have certain moves with instructions like “roll + conditions marked.” Some such moves provide better options the more desperate you are (e.g., Reveal a Shocking Truth from Pasión de las Pasiones), while others reverse the outcomes, with a 10+ being the worst outcome: e.g., Face Certain Death from Pasión de las Pasiones, “On a miss, your death was less certain than we thought; tell us about your daring escape.”

Stress

Some games use stress tracks that can be either physical or mental, allowing players to “absorb” consequences at a cost. This appears in games focusing on long-term wear and tear on characters. In Impulse Drive—

When you are directed by a Move or the SM to mark Harm, for each Harm you receive, mark off one of the Harm options [below] or mark off 1 Stress. When you have 5 Stress, clear the Stress track, and take a Calamity.

  • Just a scratch: You’re a bit banged up, but it’s nothing serious. Can be healed by choosing. “Shrug it off” when you roll Recover, or when a Scene ends.
  • I’m rattled: You’re shaken and shocked, you have Disadvantage ongoing to any +Slick or +Calculating rolls. Can be healed by choosing “Shrug it off” when you roll Recover, or when a Scene ends.
  • I’m hurt bad: You have severe bleeding or broken bones; you have Disadvantage to any roll requiring physical exertion. Can be healed by receiving Surgery.
  • I’m knocked out: You’ve been knocked unconscious and can’t move, act, or even see anything. Can be healed when an Ally chooses “First Aid” when they roll Recover, or when a Scene ends.
  • I can’t go on: Your journey is over, you pass away, unmourned and unnoticed by the vast black of space.

Calamity lists in Impulse Drive vary by playbook. Here’s the list for The Scoundrel—

When you mark an item in the Calamity list, describe the Fictional consequences mentioned in your choice and mark XP. If appropriate, you may write a Hook about it.

  • You come into possession of something extremely rare or valuable, but it’s stolen or illegal.
  • An old flame you have a complicated history with reaches out to rekindle your relationship. If you do, take your other Background Move.
  • Someone you owe a lot of money to is looking to collect the money or your head.
  • You’re faced with a choice: stay under the radar or make a big score.
  • An old lover reaches out to you for help with a problem or danger they’re facing.
  • You suffer a terrible wound, illness, or debility. Describe what you have lost.

Dice Pools

For Planet of the Week, players by default have 5 Health. The core mechanic uses a dice pool, where players count hits after rolling against a stat (ranging from 1 to 3 upon character creation, increasable to 5 as they level up). However, the number of dice they can roll is capped by their Health. This doesn’t usually affect them at first (in fact, they can spend 1 Health for an Extra Effort die, once per session), but as a session goes on, their rolls may become capped and more dramatic.

Dramatic moments come from the fiction: a PC might take Harm and then continue to suffer Harm unless they receive medical intervention.

Since Planet of the Week is episodic, inspired by television shows, players typically start each new mission with full Health again, and injuries aren’t lasting.

NPCs

Unlike traditional RPGs, NPCs (Non-Player Characters) in PbtA games often have completely different harm systems than PCs do. For instance, in Fellowship, harming an NPC removes a descriptive or prescriptive tag from them, removing that capability from them in the future. In Apocalypse World, NPCs use a different, more deadly harm clock:

When an NPC suffers harm

Innovative Examples

Some other interesting harm mechanics include—

  • Blades in the Dark: its stress and trauma system
  • Thirsty Sword Lesbians: its conditions tied to character growth
  • Avatar Legends: its balance between narrative and mechanical harm
  • City of Mist: its thematic approach to damage.

The harm system in a PbtA game does more than track damage: it creates compelling narrative moments, forces interesting choices, and reinforces the game’s themes. Whether using harm clocks, conditions, stress or innovative new approaches, the key is ensuring that harm serves the story and creates engaging gameplay moments.

This is an excerpt from my ebook, Reflections on PbtA Design.

Photo credit: Wikimedia Commons.