You cannot generate attacks of opportunity with Thorn Whip. However there is a second level spell, Spike Growth, which inflicts 2d4 per 5ft of movement. So if Thorn Whip is used to pull an enemy 10ft through spike growth, would they take 1d6 (TW) + 4d4 (SG) damage?

  • \$\begingroup\$ @KRyan I hesitated until I noticed that it starts general, but the specific real problem prompting the other question is Thorn Whip + Spike Growth. That decided it for me, at least. \$\endgroup\$ Jan 22, 2017 at 18:04
  • 1
    \$\begingroup\$ @SevenSidedDie Yup, read that too quickly. And since the ruling is that the default is involuntary counts (which I misread also), my argument as to this being an exception falls apart anyway. \$\endgroup\$
    – KRyan
    Jan 22, 2017 at 18:55

1 Answer 1


This thread addresses this issue:

Are there any rules relevant to involuntary movement and effects other than Opportunity Attacks?

That being said, the upvoted answer states:

The is no general rule (that I can find) regarding involuntary movement.

However, Jeremy Crawford - one of the lead designers for 5e and official go-to-guy for rules clarification - has said:

When a spell's description uses "enter" in relation to an AoE, the entering has to be voluntary only if the text says so.

So although Spiked Growth's text states "When a creature moves into or within the area" rather than enter, it's reasonable to assume "moves into" has the same ruling as "enter".

  • \$\begingroup\$ Hey Graydon Green, thanks for the catch. I understand you don't have enough reputation to comment on another's post but we usually just leave links to possible duplicate question under comments in the question. \$\endgroup\$
    – daze413
    Jan 22, 2017 at 8:54

Not the answer you're looking for? Browse other questions tagged .