Criticals

status : Work in progress
todo : Item Quality system

Core Critical Rule

When a creature scores a critical hit:

• Roll damage normally
• Add the maximum possible damage of the damage dice
• Apply the damage-type critical effect

Formula: Total Damage = Rolled Damage + Max Damage

When a Critical Occurs

• Weapon Attacks: Natural 20
• Spell Attacks: Natural 20
• Saving Throws: Target rolls a natural 1

If a class feature or feat already modifies critical hits, this system extends it rather than replaces it.
Magic items that have additional damage types do not get a secondary effect unless otherwise stated by the magical item. Example: A fire sword (1d6+STR+1d4 fire) on critical only applies the secondary slashing effects, not the fire critical effects.

Physical Damage

Bludgeoning

On a critical hit:

• If actively shielded, shield is targeted first.
  • Armor degrades 1 quality. (non-magical)
• Roll 1d6:
  1: Knocked prone
  2: Non-magical weapon damaged
  3: Non-magical armor damaged
  4: Agonized until their next turn
  5: Rattled until their next turn
  6: Severe bodily trauma (DM discretion)
• If the target is killed:
  • Nearby enemies of similar station make a Morale check
  • Very low intelligence creatures are immune to the Morale Check

Piercing

On a critical hit:

• The attack continues in a straight line behind the target
• Resolve additional hits without new attack rolls:
  • Use original roll result
  • Apply –5 to hit per additional creature
• Roll damage for each hit
• If a creature in the line is killed:
  • Remaining creatures are pushed 5ft
• Piercing-related features resolve first; this effect extends them

Slashing

On a critical hit:

• Target gains Bleed
• Bleed damage by proficiency bonus

• Bleed rules:
  • Damage triggers at start of target’s turn
  • Damage halves each round
  • Any magical healing ends Bleed
  • Creatures without blood or auto-healing are immune
• If the attack kills the target:
  • Attack transfers to one adjacent enemy
  • Extends cleave-style features by one additional target

Elemental Damage

Acid

On a critical hit:

• One non-magical or unprotected item is degraded or destroyed
• Severity depends on Item Craft Quality
• Magical items are immune unless stated otherwise

Cold

On a critical hit:

• Target’s speed is halved
• If the spell already slows:
  • Increase potency (duration, severity, or added disadvantage)

Fire

On a critical hit:

• Target is set on fire
• Takes 1d6 fire damage per round
• Fire lasts a number of rounds equal to item or creature quality
• Each round not addressed, damage increases by +1 until item is destroyed.
• A bonus action may be used to douse flames
• Magical items do not catch fire unless they are designed that way

Lightning

On a critical hit:

• Damage chains to adjacent creatures within 5 ft
• If no valid path exists:
  • Target is stunned until end of next turn
• Conductive terrain may extend effects (DM discretion)

Thunder

On a critical hit:

• Target has disadvantage on saving throws until end of next turn
• Effect area expands beyond target
• Brittle materials (glass, shale, porcelain) are damaged or destroyed

Magical & Energy Damage

Force

On a critical hit:

• Target is pushed back
• If movement is blocked:
  • Roll one additional damage die

Radiant

On a critical hit:

• One curse, possession, or undead-affecting property is removed or suppressed
• Target is marked with radiant light for 1d4 rounds
  • Emits light
  • Prevents concealment
  • Does not grant advantage

Necrotic

On a critical hit:

• Target’s maximum HP is reduced (DM discretion)
• If the target dies:
  • Caster regains half the necrotic damage dealt
  • If this is already a feature, increase potency

Poison

On a critical hit:

• Target gains the Poisoned condition
• If already poisoned:
  • Increase potency by raising the save DC or extending duration

Psychic

On a critical hit:

• Reduce mental ability scores (INT, WIS, or CHA) by 1
• Effect ends at the next subsequent round that the target has not received additional Psychic damage

Design Intent

• Crits are decisive, cinematic, and tactical
• Damage types matter beyond numbers
• Existing features are enhanced, not overwritten
• Environmental interaction is encouraged