Repelling Blast vs Difficult Terrain - Answered

[Master O'Laughs]

Quick question (I tried googling the answer first but no luck), does difficult terrain reduce the effects of a creature being pushed?

In a fight in CoS and our druid cast plant growth over a horde of baddies and I was wondering if my repelling blast would push the full 10 feet per blast in it.

If so, where would be the page number in the PHB for it?

Thanks for the input

[NNescio]

Quick question (I tried googling the answer first but no luck), does difficult terrain reduce the effects of a creature being pushed?

In a fight in CoS and our druid cast plant growth over a horde of baddies and I was wondering if my repelling blast would push the full 10 feet per blast in it.

If so, where would be the page number in the PHB for it?

Thanks for the input

Difficult terrain forces creatures to "move at half speed", that is "moving 1 foot in difficult terrain costs 2 feet of speed" (Movement rules, PHB-p.182). Forced movement does not use the movee's speed or movement (by definition, but this is also further supported by the opportunity attack rules under PHB-p.195), ergo difficult terrain has no effect on forced movement.

To further lend credence to the above, note that speed is a measure of voluntary movement by a creature, i.e. the "the distance in feet that the character or monster can walk in 1 round." (PHB-p.181). Ergo it has no bearing on forced movement. Likewise for effects that reduce speed, like difficult terrain.

(By RAW. A DM might rule otherwise for really 'hampering' terrain that 'logically' should prevent or hamper creatures from being dragged or pushed through them.)

[Master O'Laughs]

Difficult terrain forces creatures to "move at half speed", that is "moving 1 foot in difficult terrain costs 2 feet of speed" (Movement rules, PHB-p.182). Forced movement does not use the movee's speed or movement (by definition, but this is also further supported by the opportunity attack rules under PHB-p.195), ergo difficult terrain has no effect on forced movement.

To further lend credence to the above, note that speed is a measure of voluntary movement by a creature, i.e. the "the distance in feet that the character or monster can walk in 1 round." (PHB-p.181). Ergo it has no bearing on forced movement. Likewise for effects that reduce speed, like difficult terrain.

(By RAW. A DM might rule otherwise for really 'hampering' terrain that 'logically' should prevent or hamper creatures from being dragged or pushed through them.)

Awesome! Thanks for the clarification! :)

[Demonslayer666]

I like the idea of keeping the movement the same, but might have them make an Athletics test to stay on their feet.

[Chad.e.clark]

Specifics beat general. Generally difficult terrain costs 2x for a creature to use their movement, but specific abilities can force creatures to move. I would imagine it depends on what the exact wording of the ability is, e.g. 1)the creature uses its reaction to move up to its speed vs 2)the creature is moved.

I would say in 1, difficult terrain would hamper movement, because creature is using its speed to move. 2 does not involve creature using its speed for movement, so difficult terrain would not be in play.

[Keravath]

If something says you are pushed back 10' then you are pushed back 10' (repelling blast). If something says you use your movement to move away (dissonant whispers, glamor bard ability) then the cost of movement is doubled.

Repelling blast
"When you hit a creature with eldritch blast, you can push the creature up to 10 feet away from you in a straight line."

Thorn Whip
"if the creature is Large or smaller, you pull the creature up to 10 feet closer to you."

The Thorn Whip/Spirit Guardians combination wouldn't work as well if the distance of thorn whip was affected by reduced movement rates or difficult terrain.

Shove
"If you win the contest, you either knock the target prone or push it 5 feet away from you."

Target is pushed 5' away - not affected by difficult terrain or reduced movement.


On the other hand:

Dissonant Whispers
"On a failed save, it takes 3d6 psychic damage and must immediately use its reaction, if available, to move as far as its speed allows away from you."

Uses the targets movements and so is subject to both opportunity attacks and difficult terrain.