My rogue has some ball bearings and of course, he wants to build Claymores. He talked to me about it beforehand since he was excited. I would like to see if he can make this work, but I told him lamp oil and the like doesn't explode, but by all means, throw that pouch of lamp oil and ball bearings lit into a room and watch... slow burning ball bearings.

He has been thinking about it more and found oil of impact as an option but that is cost prohibitive for him ATM, but also he asked an interesting question: could the wizard cast a fireball into a breakable glass jar? (He got the idea from the Mad Manor of Astabar and the glass sphere in the wizard's bedroom.) I looked around but couldn't find any resources as to whether that is allowed.

Can he make that work?

The rogue and wizard in the party are level 5.


7 Answers 7


Not by RAW

A spell only does what it says in the description so fireball does not push objects with any kind of force.

Balance concerns if you ignore RAW

If you want to allow this in your game anyway (which I believe you should, it is always good to encourage creativity in your games), simply changing the damage type of the spell from fire to piercing damage shouldn't unbalance the effect.

Also, you may want to have the wizard expend resources as if they were copying a spell into their spellbook to master this variant usage of fireball. You are essentially making a homebrew spell.

The way this will likely go in practice is that the wizard will take the Ready action while the rogue throws the "claymore." Treat the item as an improvised weapon (piercing damage from the glass) and then the wizard can cast his specialized fireball (on a hit it is centered on the target, on a miss wherever the bottle ends up within 6 seconds) dealing piercing damage.

Since this uses up some additional resources in the crafting of the item, you could have it deal double damage to objects and structures (to fit the flavor a bit more too). This will rarely come up but adds a bit of flare.


The 1st level spell "Thunderwave" (PHB pg 283) has the force effect you are looking for, but the range is "self".

The "Glyph of Warding" (PHB pg 245) explosive runes has the exact effect you are looking for. Plus, the mechanics of the spell actually align with how a claymore mine is employed: "...that object must remain in its place; if the object is moved more than 10 feet from where you cast this spell, the glyph is broken, and the spell ends without being triggered."

(This answer was edited based on the feedback provided by @SevenSidedDie)


Fireball causes an "explosion of flame" [per SRD 5.1, p. 144] causing fire damage and igniting flammable objects, but nothing in the description says that it can propel objects like shrapnel.


This answer presumes that the desired effect is "ball bearings/claymore mine" and that fireball was the best you could come up with. I'll offer that there is something else available if you allow for other game items as a solution set.

Exam question: How do we get animate object into the rogue's hands, or into the hands of a fifth level party generally?

Option 1: Claymore with the Wizard participating (risk of failure)

A scroll of animate object, one time use, with the risk that since the Spell is 5th level, and the wizard is 5th level and can thus only use up to 3rd level spells, the attempt may fizzle since there is a chance that the scroll won't work. Rogue places ball bearings, wizard casts animate object from the scroll, and if DC 151 roll is made, claymore carnage proceeds as below.

Option 2: Claymore for a 5th level Arcane Trickster Rogue

If your rogue is an Arcane Trickster, then he can use wands since at level 3 the rogue acquires the spell caster feature. Otherwise, the rogue needs to wait for level 13 to use magical devices. Your wizard can use his fireballs for other challenges to the party. Or, the wizard can use the wand, as the scroll above but with no chance for failure.


  1. A wand usually requires attunement, and you'd need to have such a wand arrive in loot/trade/treasure/whatever. This means that you'd have to be OK with offering a rare magical item to your player at level 5. This might be early in terms of level/magic, but it's not too far out of the box. (See DMG rarity guidelines on magic items/treasures, there are a some rare items for Tier 2 play, page 135; rare is listed for character level "5th or higher")

  2. Not all wands require attunement by a spell caster, although the one I used as a model does. You can choose to have the proposed wand require attunement, but not require "by a spell caster" so that any rogue could use it. If you leave the attunement as shown in the original wand, then the wizard would be able to use it in any case.

Reskin the Wand of Binding to be the Wand of Animating

The Wand of Binding holds 7 charges, and can use 5 of them to cast the 5th level Hold Monster Spell, or the 2d level (2 charges) hold person spell. (Recharges 1d6+1 charges at dawn) Spell save/attack DC 17 (requires attunement by a spellcaster) (SRD p. 248)

It becomes a comparably powered item called

Wand of Animating which has 7 charges; casting Animate Object (5th level) uses five charges, casting Levitate (2d level) uses two charges. (Recharges 1d6+1 charges at dawn) Spell save/attack DC 17 (Optional: requires attunement by a spell caster)

Why Animate Object?

Animate Objects 5th-­‐‑level transmutation
Casting Time: 1 action
Range: 120 feet Components: V, S
Duration: Concentration, up to 1 minute (This allows you to delay!)

{snip} Choose up to ten nonmagical objects within range that are not being worn or carried.

I think we can safely call a ball bearing a tiny object. :)

{snip} Tiny, +8 to hit, 1d4 + 4 damage (Table in spell description)
{snip} If you command an object to attack, it can make a single melee attack against a creature within 5 feet of it. It makes a slam attack with an attack bonus and bludgeoning damage determined by its size.

Here's your claymore:

  1. Put 10 ball bearings on the ground, in a bowl, in a helmet, or whatever suits your rogue.

  2. Use the wand to cast animate object and then (here is the delay part) when the time is just right, command the ball bearings to attack. You have up to one minute, depending upon how long you delayed. The text says that an object can attack a single creature, so this as much a "shotgun" as a claymore. However, you can get the "pattern" effect if you as DM interpret the spell to allow each ball bearing to attack any creature within range ... I can see that going either way for this application of that spell. (You are already home brewing a bit, so why not?)

The wand wielder rolls 10 "to hit" rolls. For each ball bearing that hits does 1d4+4 damage. A max possible 10d4 + 40, but he'll probably miss a few ... and if a few crit, so much the better!

The above procedure makes the claymore mine usable once per recharge cycle. (Unless the recharge cycle d6 roll stinks)

  • Final Caveat: as @Szega notes, one reading of this spell text is that the ball bearing can make one attack for as long as your caster/wand wielder can concentrate on the spell. That would make this much more lethal than a "one shot blast" since each ball bearing could attack for up to 10 rounds. If you feel that is too powerful, you can reduce the number of rounds that the ball bearings can attack, or, you can go ahead let it be awesome claymore carnage for that one big blast of the adventuring/recharge day. The limiting factor there becomes whether or not the rogue or wizard can maintain concentration. As the players go up in level, the HP of opponents will tend to handle the damage better, which is part of why I made the earlier caveat about rare items and character levels. (A scroll is the more conservative approach).

    I added levitate as the 2d level spell for the wand since it seems thematic to moving things around with magic. It isn't necessary to be on the wand, and could be removed without harming your desired effect of a claymore making method using what's available in the rule book, with a slight tweak.

Note: I totally stole this idea from a player in our game whose wizard does exactly this with ball bearings and animate objects. He's 11th level. Our DM rules that they all attack at once, which I like to call "the shotgun blast" effect. But "personal claymore" works fine. :)

1 From Spell Scroll (DMG):

If the spell is on your class’s spell list but of a higher level than you can normally cast, you must make an ability check using your spellcasting ability to determine whether you cast it successfully. The DC equals 10 + the spell’s level. On a failed check, the spell disappears from the scroll with no other effect.


You don't need a fireball.

gunpowder exists in 5th edition so you could just make a landmine, and you won't need a fireball to set it off, Prestidigitation will set off a jar of black powder or any other gunpowder trap. Although keep in mind it will not as powerful as a modern claymore mine, there is a big difference between black powder and plastic explosives.

Considering trap style landmines have existed since the 13th century it is not unreasonable your character could not make a purely mundane mechanical landmine or explosive boobytrap.

gunpowder rules can be found on pages 267-268 of the 5th Edition Dungeon Master's Guide

Gunpowder is chiefly used to propel a bullet out of the barrel of a pistol or rifle, or it is formed into a bomb. Gunpowder is sold in small wooden kegs and in water resistant powder horns. Setting fire to a container full of gunpowder can cause it to explode, dealing fire damage to creatures within 10 feet of it (3d6 for a powder horn, 7d6 for a keg). A successful DC 12 Dexterity saving throw halves the damage. Setting fire to an ounce of gunpowder causes it to flare for 1 round, shedding bright light in a 30-foot radius and dim light for an additional 30 feet.

Of course if you want to make an explosion in medieval times all you really need is a lot of flour, a room with little airflow, and candle, grain silo explosions are deadly. spread the four dust in the air, then you need a jar with a few holes over the candle tired of a sting tied to the door and you have an explosive trap. A decent trap but not a good landmine.


I'd like to propose a different option to build something like a claymore mine:

You could let the Wizard inscribe the glyph of warding into something like a small metal cylinder, then put this into a jar filled with all kinds of nasty shranpnel. The spell says that you can store an explosion or a spell, so you can just go for the explosion option. Now, set a trigger and wait for an explosion to go off, ripping apart the jar and propelling the shrapnels around (Considering the wikipedia definition of an explosion telling you that it usually produces a huge amount of motion energy). You could argue this would deal maybe 1D6 bonus piercing damage on top of the explosion.

You would however need to build this at the location where the mine is going to be placed to not break the spell.


Use the tool proficiency rules in Xanathar's Guide to Everything

Xanathar's Guide contains optional rules for tools which include special uses only available if you're proficient with them. The special use for Thieves' Tools is setting traps.

Just as you can disable traps, you can also set them. As part of a short rest, you can create a trap using items you have on hand. The total of your check becomes the DC for someone else’s attempt to discover or disable the trap. The trap deals damage appropriate to the materials used in crafting it (such as poison or a weapon) or damage equal to half the total of your check, whichever the DM deems appropriate.

It's a very bare-bones system, but it does require that the player have appropriate materials, puts you (the DM) in control of the damage, and is difficult to abuse since it takes 1 hour to set up 1 trap.

At that point it's just a matter of determining how much damage you feel is appropriate and what the cost of the materials should be. DMG Chapter 5 has guidelines for designing traps and Chapter 8 has a guidelines for improvising damage; you can use either of these to determine how powerful the effect should be.


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