One of my players is constantly bugging me about using Enlarge/Reduce to reduce a boulder to a smaller size and then hurl it via the spell Catapult, cancel the concentration on Enlarge/Reduce before the impact, and let the enemy be smashed by a much bigger one.

Can the Enlarge/Reduce and Catapult spells be combined in this way?

  • 3
    \$\begingroup\$ Welcome to RPG.SE! Take the tour if you haven't already and see the help center or ask us here in the comments (use @ to ping someone) if you need more guidance. Good Luck and Happy Gaming! \$\endgroup\$
    – Someone_Evil
    Feb 23, 2020 at 12:08
  • 1
    \$\begingroup\$ In general questions like "Do you think it"s possible?" should be avoided. It would be preferrable to clarify, if you're asking a rules question or a recommendation on rulings based on the situation at the table. In this situation it seems to be a rules question!? \$\endgroup\$
    – fabian
    Feb 23, 2020 at 12:22

2 Answers 2


Yes this will work, but...

First off, Enlarge/Reduce can certainly make boulders smaller:

The target's size is halved in all dimensions, and its weight is reduced to one-eighth of normal.

However, these boulders have to meet the requirements below for Catapult to shoot them:

Choose one object weighing 1 to 5 pounds within range that isn’t being worn or carried.

So, you're looking at a boulder that is at most 40 pounds in weight. How big is that? I don't make a habit of wandering around the countryside weighing rocks, but if I had to guess I'd say probably a little bigger than your head. So far, we're good to go...


D&D 5e doesn't make rules to handle things like mass, inertia, coefficients of drag, and muzzle velocity...so all we're left with is the actual spell description. And, according to the Catapult spell:

the object and what it strikes each take 3d8 bludgeoning damage.

So, yes you can totally Reduce a boulder to a size that the Catapult spell will work on it, and yes you can even drop concentration after it is shot toward a target, but the spell does 3d8 bludgeoning damage. Period.

The damage comes from the spell, not from what you use as the projectile. You can use a pound of soft butter, 3d8 damage. A pound of feathers, 3d8 damage. You can Reduce a boulder, 3d8 damage.

  • 13
    \$\begingroup\$ Honestly, 3d8 is the best case scenario. The DM could just as well rule that catapult spell ends as soon as the reduce spell on the boulder is ended, since the boulder is now an invalid target. In the case, the target takes no damage at all. \$\endgroup\$ Feb 23, 2020 at 15:13
  • 2
    \$\begingroup\$ @RyanC.Thompson In that case, draw a line diagonally vertically to a space above the target. When the object arrives at that space, drop Enlarge/Reduce. It is now a boulder falling for 90 ft. \$\endgroup\$
    – Axoren
    Feb 23, 2020 at 20:43
  • 4
    \$\begingroup\$ @Axoren in which case, you probably need a check to release it at ... just .. the ... right ... moment \$\endgroup\$
    – Yakk
    Feb 24, 2020 at 23:25
  • 3
    \$\begingroup\$ @Axoren Huh? You are trying to place a rock at a spot 90' above a target, dropping concentration at the exact moment, well enough that it falls and hits someone who cannot get out of the way before it does. How is requiring a check of some kind a dangerous precedent here? I mean, I could say "no". I could say "the catapult spell includes the object falling to the ground, so hitting while falling to the ground also uses the catapult spell rules". Or I could ask for a check for the precision of the work you are doing. \$\endgroup\$
    – Yakk
    Feb 25, 2020 at 1:52
  • 1
    \$\begingroup\$ @Axoren Yes, and dropping a rock exactly on someone's head from 90' up is something you can fail at doing in D&D. You aren't even there, so you can't even eyeball when you are directly above the target. If I had a device that let me teleport a rock to a location and direction of my choice with 100% accuracy (I would have to point, and I'd have to say how far), having that location be just right so it drops on someone's head would be not trivial; I could do it with a laser rangefinder and trig? Why wouldn't there be a check involved? \$\endgroup\$
    – Yakk
    Feb 25, 2020 at 13:28

Can the Enlarge/Reduce and Catapult spells be combined in this way?

See, the thing is, in this case it's "ask your DM". So, whatever you decide, goes. I'm gonna say 'no' for three very different reasons.

One, the Catapult spell. It clearly says what damage it does.

Two, the timing. Doing something like that - dropping concentration at just the right time would be certainly nontrivial and, even if allowed, ought require some kind of difficult check.

Three, I have a personal hatred of enlargement and shrinking as superpowers and magical effects, and my personal ruling would be that the light fast pebble becomes a heavy slow boulder which immediately falls to the ground, because conservation of momentum. But then, I'm a spoilsport.


You must log in to answer this question.

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