Gaseous Form 5e: Movement, Resistance, and Spell Limits

I’ve always enjoyed Gaseous Form as a spell that solves the locked-door problem by changing the adventurer instead of the lock. Its mist form is excellent for infiltration and escape, but the 10-foot speed and severe action limits keep that freedom from being effortless.

Gaseous Form 5e — Quick Spell Reference

How Gaseous Form Works in 2014 D&D 5e

You touch one willing creature and transform it, along with everything it is wearing and carrying, into a misty cloud. The effect lasts for up to 1 hour while you maintain concentration, and it ends early if the target drops to 0 hit points. An incorporeal creature cannot be affected.

The target’s only movement is a 10-foot flying speed. It can hover, cannot fall, and remains aloft even while stunned or otherwise incapacitated. It may also enter and occupy another creature’s space, though doing so does not deal damage or automatically hide the mist.

Passing Through Cracks, Doors, and Liquids

The mist can pass through small holes, narrow openings, and even mere cracks. It cannot pass through completely solid material, so a sealed container or a door without any opening still blocks it.

Liquids are treated as solid surfaces. The target cannot flow into water, travel through a flooded tunnel, or sink through another liquid merely because it is gaseous. Rain presents a less explicit case: the spell does not define how separate falling droplets interact with the cloud, so any effect beyond ordinary weather is a DM ruling.

What Can a Creature Do in Gaseous Form?

The target cannot talk, manipulate objects, attack, or cast spells. Anything it was carrying becomes part of the transformation and cannot be dropped, used, or otherwise handled until the form ends.

Those limits rule out opening a door from the far side, drinking a potion, using thieves’ tools, or casting a spell after slipping into a room. The target can still move and can take actions not prohibited by the spell when they are actually possible in mist form, but the text does not grant new actions beyond its movement and defensive benefits.

If the caster targets themself, the spell does not automatically end. They can continue concentrating even though they cannot cast another spell. Normal events that call for a concentration saving throw still do so.

What Damage Does Gaseous Form Resist?

The 2014 target has resistance to nonmagical damage. This wording is broader than resistance to nonmagical weapon attacks: when a damage source is nonmagical, the target halves that damage unless another rule says otherwise.

The spell does not grant immunity. Magical damage applies normally, as does any non-damage effect whose requirements can affect the cloud. The target also has advantage on Strength, Dexterity, and Constitution saving throws, but not on ability checks or on Intelligence, Wisdom, or Charisma saves.

Can Gaseous Form Be Upcast?

The 2014 spell has no higher-level benefit. Using a 4th-level or higher slot does not add targets, increase the flying speed, or extend the duration. That is one of the important differences from the 2024 version.

Tactical Uses and Tradeoffs

Gaseous Form is useful for scouting through tiny openings, escaping ordinary restraints, reaching ledges, and transporting a willing creature through a route that solid bodies cannot use. Hovering makes vertical movement safe, but the 10-foot speed is slow: even Dashing covers only 20 feet in a turn.

The spell is poor for fighting and manipulating the environment. It can also strand a target on the wrong side of a sealed barrier if the caster loses concentration before the target finds a viable return path.

Gaseous Form: 2014 vs. 2024 Rules

The 2024 version makes several material changes:

• The target can end the spell on itself with a Magic action.
• Resistance changes from all nonmagical damage to Bludgeoning, Piercing, and Slashing damage, whether that weapon damage is magical or not.
• Immunity to the Prone condition is stated directly.
• The prohibition against targeting an incorporeal creature is removed.
• The material component is a bit of gauze; the wisp of smoke is removed.
• A higher-level slot can affect one additional creature per slot level above 3rd.

The 10-foot Fly Speed, hovering, physical restrictions, save advantages, and liquid barrier remain central to both versions.

Gaseous Form FAQ

Can you cast Gaseous Form on yourself?

Yes. You are a willing creature you can touch, and the spell does not forbid self-targeting.

Can Gaseous Form move through a keyhole?

Yes, if the keyhole provides an actual opening. The spell permits even mere cracks but does not allow movement through uninterrupted solid matter.

Can a gaseous creature attack or cast spells?

No. Both actions are explicitly prohibited while the form lasts.

Can Gaseous Form travel underwater?

No. The target treats liquids as solid surfaces.