The Endlessness
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Critical Hits in D&D 5e: How They Work

D&D 5e critical hits. Double dice, when crits happen, expanding crit range with Champion, and why crits matter.

Critical Hits in D&D 5e: How They Work

A critical hit (crit) happens on a natural 20 on attack rolls. You deal bonus damage.

The Core Rule

  • Natural 20 on attack roll: Automatic hit + bonus damage.
  • Bonus damage: Roll double the damage dice (not modifiers).

Example:

  • Longsword attack hits for 1d8 + 3 normally.
  • Critical hit: 2d8 + 3.

Expanded Crit Range

Champion Fighter

  • Level 3: Crit on 19-20.
  • Level 15: Crit on 18-20.

Increases crit probability from 5% to 10% (then 15%).

Hexblade's Curse (non-SRD)

Crit on 19-20 against cursed target.

Other features

Few official ways to expand crit range. Mostly Champion.

Crit Damage

Paladin Divine Smite on a crit:

  • 3rd level slot smite: 3d8 + 2d8 (fiend/undead bonus) = 5d8.
  • On crit: 10d8 + weapon damage doubled.

Massive burst.

Crit Fishing Builds

Champion Fighter + GWM

  • Champion's crit range (19-20 at 3, 18-20 at 15).
  • GWM's bonus action attack on crit or kill.
  • More attacks = more crit chances.
  • Half-Orc's Savage Attacks = extra damage die on crit.

Classic crit fisher.

Paladin Smite Combos

Divine Smite on crit doubles all smite dice. Burst damage specialists.

Advantage and Crits

Advantage doubles crit chance (roll twice, take higher).

  • Normal: 5% crit chance.
  • Advantage: 9.75% crit chance.

Barbarian Reckless Attack + Champion = consistent crits.

Auto-Crits

Some conditions force auto-crits:

  • Paralyzed target in melee: Auto-crit.
  • Unconscious target in melee: Auto-crit.

Setting up paralysis (Hold Person) = auto-crits on hits.

Nat 1s (Critical Misses)

Nat 1 auto-misses. In some house rules, extra bad things happen (drop weapon, self-damage). In RAW, just a miss.

In The Endlessness

Our AI Dungeon Master handles crit mechanics: double dice, expanded ranges, auto-crits from paralysis.

For related reads, our advantage and disadvantage, fighter guide, and paladin guide cover more.

Final Takeaway

Crits are game-changers. Build around them (Champion, Half-Orc) or exploit them (Paladin Smite).

Start a crit build at The Endlessness.

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