Moonbeam — Complete D&D 5e Spell Guide

Table of Contents

• •Quick Answer
• •Overview
• •Stat Block
• •When NOT to Use This
• •Spell Slot Efficiency
• •Pro Tips
• •Common Mistakes to Avoid
• •Usage Tips
• •Rules Notes
• •Synergies
• •Anti-Patterns
• •Tactical Modules
• •Countermeasures
• •Moonbeam in the 2024 Rules
• •Related Guides and Tools
• •Frequently Asked Questions

Quick Answer

Moonbeam is a 2nd-level druid evocation. It creates a 5-foot-radius, 40-foot-high cylinder of moonlight within 120 feet for up to 1 minute (concentration). Under the 2014 rules, a creature takes 2d10 radiant damage (Constitution save for half) when it enters the beam for the first time on a turn or starts its turn there. You can spend your action on later turns to move the beam up to 60 feet.

Overview

Moonbeam is a 2nd-level evocation spell that pins a column of damaging moonlight on the battlefield for up to a minute. Druids get it at 3rd level, and it stays useful for the whole campaign because it scales by 1d10 per slot level. Each trigger deals 2d10 radiant damage, 11 on average, or half on a successful Constitution save. Shapechangers save with disadvantage and are forced back into their true form if they fail.

The catch is timing. In the 2014 rules, the beam does not hurt anyone the moment you cast it. Damage happens when a creature starts its turn inside it or enters it. Moving the beam also costs your action each time. Moonbeam is strongest against slow or stuck enemies, and in narrow spaces where enemies must walk through it. It is weak against fast enemies who simply step out.

Stat Block

When NOT to Use This

• •Against fast enemies with nothing holding them in place. A creature that walks out of a 10-foot-wide beam on its turn takes damage once at most.
• •When you will need your action every turn for other spells. Moving the beam uses your action (a Magic action in 2024).
• •When your concentration is already holding something better, such as Entangle or Conjure Animals.
• •Against a single enemy you could control instead. A 2nd-level slot spent on Hold Person or Spike Growth can matter more in a short fight.

Spell Slot Efficiency

When worth the slot: Fights that will last several rounds, enemies that are grappled, restrained, or boxed in, chokepoints, and shapechangers.

When NOT worth the slot: Short fights, very mobile enemies, or rounds where you need your action for healing or control.

Pro Tips

Tip #1: Place it where enemies will start their turn.

Why it works: In 2014 rules, damage comes from starting a turn in the beam or entering it. A creature that is grappled, restrained, or blocked in will start several turns inside.

This avoids the mistake of: Casting it on a creature and expecting damage right away.

Tip #2: Combine it with forced movement.

Why it works: Thunderwave pushes creatures 10 feet. Pushing an enemy into the beam on your turn is commonly ruled as entering the area, which triggers the save. Confirm with your DM, since forced movement into an area is a table call in 2014 rules.

This avoids the mistake of: Spending your action to move the beam when you could move the enemy instead.

Tip #3: Save it for shapechangers.

Why it works: A shapechanger makes the save with disadvantage. If it fails, it reverts to its true form and cannot change shape again until it leaves the light.

This avoids the mistake of: Treating Moonbeam as plain damage when it can also strip a lycanthrope or doppelganger of its disguise.

Tip #4: Upcast when the fight will be long.

Why it works: Each slot level above 2nd adds 1d10 to every trigger, not just the first one. A 4th-level Moonbeam deals 4d10, 22 on average, every time it triggers.

This avoids the mistake of: Comparing Moonbeam to one-shot spells by its first round of damage only.

Common Mistakes to Avoid

Expecting damage on the turn you cast it (2014 rules).

Why it's bad: The 2014 text only triggers when a creature enters the area for the first time on a turn or starts its turn there. Casting it on top of an enemy does nothing until that enemy's turn starts.

Do this instead: Cast it where enemies will begin their next turn. If you play the 2024 rules, creatures in the area save as soon as the beam appears.

Assuming that moving the beam onto a creature damages it (2014 rules).

Why it's bad: Read literally, the 2014 trigger is the creature entering the area, not the area moving onto the creature. Many tables rule that moving the beam onto an enemy does not deal damage until that enemy's turn starts. This is the most common Moonbeam argument at the table, so settle it with your DM before the fight.

Do this instead: Move the beam onto enemies so they start their turn inside it. Under 2024 rules, moving the beam into a creature's space does trigger a save.

Forgetting that a creature only takes damage once per turn.

Why it's bad: In 2014, entering triggers only "for the first time on a turn." A creature that walks in and out of the beam several times on one turn still saves only once.

Do this instead: Count triggers per turn, not per square moved.

Dropping concentration by standing in the open.

Why it's bad: Every hit forces a Constitution save, DC 10 or half the damage taken, whichever is higher. Losing concentration ends the beam.

Do this instead: Cast from range. The spell reaches 120 feet, so you can stay well behind the front line.

Usage Tips

• •Worked example: a 3rd-level druid with 16 Wisdom has a spell save DC of 13 (8 + 2 proficiency + 3 Wisdom). An ogre has +3 to Constitution saves, so it succeeds on a 10 or higher and fails 45% of the time.
• •On a fail it takes 11 damage on average. On a success it takes half, rounded down, which averages 5.25. Each trigger is worth about 7.8 expected damage (0.45 × 11 + 0.55 × 5.25).
• •If the ogre is grappled and starts 4 turns in the beam, that is about 31 expected damage from one 2nd-level slot. The ogre has 59 hit points.
• •Against a werewolf (Constitution save +2) the same druid does better. Disadvantage means the werewolf must succeed on both dice, needing 11 or higher on each. It succeeds 25% of the time and fails 75%, so each trigger averages about 9.6 damage, and a failed save forces it back into its humanoid true form.
• •Upcast math: each slot level adds 1d10, or 5.5 average, to every trigger. Use the damage calculator to compare it against your other options at a given level.

Rules Notes

• •The cylinder is 5 feet in radius (10 feet across) and 40 feet high. It fills with dim light.
• •2014 trigger: a creature that enters the area for the first time on a turn, or starts its turn there, makes a Constitution save. It takes 2d10 radiant damage on a fail or half on a success.
• •Shapechangers save with disadvantage. On a failed save they revert to their original form and cannot take another form until they leave the light.
• •On each of your turns after you cast it, you can use your action to move the beam up to 60 feet in any direction.
• •Moving the beam is not casting a spell. You can still cast a bonus-action spell such as Healing Word on that turn.
• •Upcasting adds 1d10 per slot level above 2nd.
• •The material component has no listed cost and is not consumed, so a druidic focus covers it.

Synergies

• •Thunderwave: a druid can push enemies into the beam. See the Thunderwave guide for the push rules.
• •Grapplers and restraining effects: a creature that cannot leave starts every turn in the beam. Enemies held by the Entangle spell are restrained, but Entangle also needs concentration, so another caster has to hold it.
• •Chokepoints and doorways: enemies that must pass through the beam to reach you trigger it as they enter.
• •Melee allies and summoned creatures: they can block or grapple enemies so they stay in the light.

Anti-Patterns

• •Moving the beam every round to chase one fast enemy. You spend your whole turn for one save.
• •Casting it in the first round of a fight that ends in the second round.
• •Holding it while you are the party's only healer and allies are dropping.

Tactical Modules

• •Chokepoint Lantern. When to use: A corridor or doorway enemies must cross. Synergy: Every creature that enters makes a save, and you keep your action free for other things.
• •Grapple Grill. When to use: A fighter or monk has grappled a dangerous enemy. Synergy: The grappled creature starts each turn inside the beam.
• •Shapechanger Reveal. When to use: You suspect a doppelganger, lycanthrope, or other shapechanger. Synergy: A failed save forces its true form and locks it while it stays in the light.

Countermeasures

• •Threat: Enemies spread out and keep moving — Response: Place the beam on the space they must reach, such as the cleric they are trying to hit. Fallback: Drop it and cast something else next turn.
• •Threat: Archers targeting your concentration — Response: Use the 120-foot range and hard cover. Fallback: If it breaks early, decide whether the rest of the fight is worth a second slot.
• •Threat: A creature with resistance to radiant damage — Response: Use the beam for its area denial and light instead. Fallback: Switch to a spell with a different damage type.

Moonbeam in the 2024 Rules

The 2024 Player's Handbook rewrites the triggers, and the changes favor the caster. Creatures in the cylinder make the save as soon as it appears. A creature also saves when the beam moves into its space, when it enters the area, and when it ends its turn there. Each creature saves only once per turn. Moving the beam takes a Magic action and moves it up to 60 feet.

The shapechanger rule is broader and gentler. There is no longer disadvantage for shapechangers. Instead, any creature that is shape-shifted, for example by the Polymorph spell, reverts to its true form on a failed save and cannot shape-shift until it leaves the cylinder. The material component is now a moonseed leaf. Damage, size, range, duration, and the upcast bonus are unchanged. Druids remain the class that gets it.

Related Guides and Tools

• •Thunderwave: the druid's push spell, for forcing enemies into the beam.
• •Call Lightning: another druid spell you re-trigger with your action every turn.
• •Concentration rules: how the save to keep Moonbeam running works.
• •Grappled and Restrained: the conditions that hold enemies in the light.
• •Roll the base damage in the dice roller, or browse every spell guide.

Frequently Asked Questions

How does Moonbeam work in 5e?

You create a 10-foot-wide, 40-foot-high column of light within 120 feet. In the 2014 rules, a creature makes a Constitution save when it enters the column for the first time on a turn or starts its turn there. It takes 2d10 radiant damage on a fail or half on a success. You can use your action on later turns to move the column up to 60 feet.

Does Moonbeam do damage when you cast it in 5e?

Not under the 2014 rules. The beam only damages creatures that enter it or start their turn in it, so a creature caught at casting takes damage when its turn starts. Under the 2024 rules, every creature in the area makes the save as soon as the beam appears.

Does moving Moonbeam onto a creature deal damage?

In the 2024 rules, yes, because the spell says creatures save when the area moves into their space. In the 2014 rules the text only mentions creatures entering the area, so many tables rule that moving the beam onto a creature does not damage it until its turn starts. Ask your DM which reading they use.

Is Moonbeam concentration in 5e?

Yes. Moonbeam lasts up to 1 minute and requires concentration. Taking damage forces a Constitution save to keep it, and casting another concentration spell ends it.

Can Moonbeam hit a creature twice in one round?

It can trigger once per turn, so a creature can take damage more than once per round across different turns. For example, an enemy can start its own turn in the beam and later be pushed back into it on your turn. It cannot trigger twice on the same turn.

Is Moonbeam good in 5e?

Yes, for druids who can keep enemies in it. It deals 2d10 radiant per trigger for up to 10 rounds from one slot and scales by 1d10 per slot level. It is weaker against mobile enemies because moving the beam costs your action.

Does Moonbeam work on Wild Shape or Polymorph?

Under the 2014 rules, only creatures with the shapechanger trait get the special rule, so a polymorphed or wild-shaped creature just takes the damage. Under the 2024 rules, any shape-shifted creature that fails the save reverts to its true form and cannot shape-shift until it leaves the cylinder.

Can Clerics or Paladins cast Moonbeam in 5e?

Moonbeam is on the druid spell list in both the 2014 and 2024 rules. Other classes need a feature that grants druid spells or a subclass list that includes it.

Citations: api:spells/moonbeam; SRD 5.1; SRD 5.2.1

Includes SRD content per CC BY 4.0. Sources: dnd5eapi.co, System Reference Document 5.1 and 5.2.1.