Catapult spell uses / mechanics

[TheFryingPen]

XGtE page 150. I don't know if it is allowed to paste the full description here.

I've been thinking of this lately. My guess is the spell isn't really anyone's first choice (only single target, only damage, save negates all damage) for killing things. Which is the only thing it does, at first glance. So I was thinking "what else could it do?"


The obvious one: Hurl items like Acid / Alchemist Fire to increase the damage. This depends a bit on the DM since these items only give the option to throw them via an Action, but since it's clear the contents are of damaging nature, it's not far fetched to allow this. Even if enemies succeed on the save, when you throw the object along a line that collides with the floor, you can deliver the contents to any square you want.
You can align the line to be able to hit multiple enemies - that way even if the first succeeds the saving throw it can hit another.
"Reflect" thrown weapons. Arrows/bolts would be too light to be targeted, but as soon as something like a Javelin leaves the opponent's hand, it theoretically becomes a viable target. So ready the spell to be cast on a weapon which is going to get thrown and negate the attack while throwing it back into your enemies.
Deny unarmed / disarmed enemies access to nearby weapons... by catapulting them into another one.
Use it as a low level version of telekinesis for fetching things - you can specify how far you want to catapult the object, so you don't risk breaking it.
Destroy single objects without setting everything on fire.
Throw some torches / lamps around in case you want to do that anyway.
Attack around corners / invisible foes: you only need to see the object you target with the spell, you can catapult it to and through spots you aren't able to see.
Stay low profile: when you can hide / subtle cast it, there's no indication that you're the source of the spell. In the right circumstances, it could look like another (N)PC has thrown something. It might even start an argument between enemies without anyone noticing you.
Similar to the previous one: create a distractions that come from a different direction (up to 150 feet away!). Bonus points if you hurl something with a Magic Mouth ("lands on ground"-trigger) on it.

[BeefGood]

I’ve been wondering about the trajectory of the object.
“Flies in a straight line” is clear enough but “before falling to the ground” is not clear. Does it fall straight down, or does physics take over and it falls along a parabolic trajectory?

[Exocist]

Everyone knows the Catapult spell is inferior to the Trebuchet spell anyway

The Catapult spell can only hurl a 5 pound projectile over 90 feet, the Trebuchet spell can hurl a 90kg projectile over 300 meters.


I’ve been wondering about the trajectory of the object.
“Flies in a straight line” is clear enough but “before falling to the ground” is not clear. Does it fall straight down, or does physics take over and it falls along a parabolic trajectory?

Imagine something shot out of a gun or cannon - they fly in a relatively straight line while they have enough momentum, but the minute they lose enough momentum gravity takes over and they start falling. In this case, 90 feet is the maximum distance the catapulted object can fly before it loses enough momentum such that it no longer becomes effective. The actual object might land a bit further than 90 feet away (due to bouncing and whatnot), but once it hits roughly 90 feet it is no longer effective as a damaging projectile.

[Vogie]

The main problem with it is that it specifies that the targeted objects "isn't being worn or carried"... so you'd have to set down your Molotov cocktails down before you can launch them towards the targets.
You can't use it as a reaction, so you can't use it to deflect or redirect arrows or javelins, although once they're shot/thrown and just lying around they're fair game.

You can totally have small things within 60 ft just launch themselves towards you... although your DM may require you to make a Dex Save to catch it rather than take damage.
Throwing things out windows or off the ship
Since you're not targeting a creature, you could definitely use it to find Invisible creatures by catapulting benches, planks, and bags of flour
It only requires somatic components, it's very easy to hide even without using Subtle Spell. If someone isn't looking directly at you, they won't know why the object started moving.
You can move anything. So, for example, a high level sorcerer could launch a delayed blast fireball, then use a quickened Catapult to launch that glowing bead at a right angle from the original location.
Depending on your campaign, the availability of mines, grenades, or explosive runes will increase the viability of the spell.


I love the idea of telekinetic characters, but the main low-level "telekinetic" abilities are just spread all over various classes. Cordon of Arrows only on the Ranger List, a slightly refluffed Spiritual Weapon only on the cleric list, Catapult only on the Sorcerer list. The only way to get an invisible mage hand is by being an Arcane Trickster Rogue. And the closest telekinetic cantrip is Eldritch blast (I like viewing it as launched Ball bearings, a la X-men 2), which is of course a warlock spell.

[Platypusbill]

Imagine something shot out of a gun or cannon - they fly in a relatively straight line while they have enough momentum, but the minute they lose enough momentum gravity takes over and they start falling. In this case, 90 feet is the maximum distance the catapulted object can fly before it loses enough momentum such that it no longer becomes effective. The actual object might land a bit further than 90 feet away (due to bouncing and whatnot), but once it hits roughly 90 feet it is no longer effective as a damaging projectile.

It's not so much about loss of momentum. Air resistance has a negligible impact on the velocity of a small, dense projectile at short distances; the bigger factor would be the accelerating downward motion of gravity.

Anyway, the text explicitly says that the object flies in a straight line. I would assume that rather than throwing the object in an arc, the spell telekinetically moves it in the desired trajectory while keeping it aloft, until it reaches the end of its travel. That would explain how the object abruptly drops past a certain range.



The main problem with it is that it specifies that the targeted objects "isn't being worn or carried"... so you'd have to set down your Molotov cocktails down before you can launch them towards the targets.


Well, you get one free object interaction per turn, so you could presumably pull out a projectile and drop it before launching it with the spell.



You can't use it as a reaction, so you can't use it to deflect or redirect arrows or javelins, although once they're shot/thrown and just lying around they're fair game.


You can't use it spontaneously like Shield or Counterspell, but OP explicitly mentioned the Ready action. It allows you to cast any spell with a casting time of 1 action in response to a trigger you specify, though it eats both your action and your reaction.



The only way to get an invisible mage hand is by being an Arcane Trickster Rogue.


Or play the Gith from MToF. Both subraces get an invisible mage hand that is also cast without verbal/somatic components.



Someone asked Jeremy Crawford (https://twitter.com/jeremyecrawford/status/910551908082839552) if you could chuck a bunch of oil flasks and Alchemist's Fire at an enemy, but he only responded "Catapult works on 1 object, not 5". Now, "1 object" is IMO completely arbitrary because anything that is not made up of just one material will consist of multiple parts, and you could simply tie up the flasks into a bundle. That said, that much damage out of a level 1 spell and some moderately expensive materials is a little excessive, so a DM might rule against it for the sake of balance. But if not, you could theoretically deal absurd single-target damage by using Catapult to throw harmful substances at an enemy.

[Dalebert]

Imagine something shot out of a gun or cannon - they fly in a relatively straight line while they have enough momentum, but the minute they lose enough momentum gravity takes over and they start falling.

It's falling immediately while also moving in the direction fired. That's why if you drop an object at the same moment you fire a bullet parallel to the ground, they will hit the ground simultaneously. This is why you arc it upward to make it go farther. Gravity has to negate the upward momentum and then it has farther to fall.

But don't mix science and d&d. Just have the object stop where the spell says it would.

[Rixitichil]

Other Possible Useful Objects to Throw:
Bag of Flour: Likely to reveal invisible Foes or at least make them easier to track
Flask of Oil: Covers target hit with oil, setting up a combination attack with a follow up fire spell.
Bag of Ball Bearings or caltrops: The Bag will likely burst and scatter them everywhere, making footing difficult.
Using alchemical flasks

Readying a Catapult spell to target an arrow in flight is an interesting idea that might just work.
A lot of these depend on a DM willing to work with your creativity, but even if they only partly work it becomes a lot more interesting than just damage.

[Lord Vukodlak]

You could perhaps use it to throw a net. The spell deals buldgeoning damage to the target and object. Nets are only destroyed by slashing.

[sophontteks]

Use it with subtle spell to make it appear as if an item is cursed, all while dealing damage.