# How do the rules handle dropping an extremely heavy object from far up to create an explosive effect? [duplicate]

The situation is as follows:

Boris is a 13th level Illusion Wizard. Boris and his party have proximity to BBEG's hideout city and want to do as much damage as possible to both the city (buildings & infrastructure) and its inhabitants. They have a plan:

They have a method for reaching a height of up to 1km above ground level (whether it be an airship or repeated casts of the Fly spell), and Boris has a plan for eviscerating the BBEG's evil city. He flies up 1km above the city, and begins casting Creation at 7th level to create a 25ft long pointed Tungsten rod in mid air over the city. Tungsten, as per (somewhat rough) 5e rules, should be classed as a non-precious metal - so the rod lasts for a total of 12 hours.

Immediately after being cast, it should begin falling towards the city, and quickly reach terminal velocity. Moments before it hits ground, Boris will use his 6th level feature Malleable Illusions to change the form of the Rod to a 3375 ft3 cube of pure tungsten. The cube has a mass of ~ 1844.5 Metric tonnes (1,844,488.46 kg or 4,066,400.99 lbs for reference), and impacts directly in the centre of the city. In the real world, if an object such as that had enough mass & velocity, it could generate explosive force equivalent to an atomic explosion.

Assuming any direct reference to how this would function in real life, some form of explosion (AOE damage) would be caused.

According to the rules what happens if I do this? What effects does it cause?

What rules exist that would relate to this scenario - specifically - to the idea that simply dropping an extremely heavy object would displace (with explosive force) a large area of mass at its impact?

## marked as duplicate by Rubiksmoose♦ dnd-5e StackExchange.ready(function() { if (StackExchange.options.isMobile) return; $('.dupe-hammer-message-hover:not(.hover-bound)').each(function() { var$hover = $(this).addClass('hover-bound'),$msg = $hover.siblings('.dupe-hammer-message');$hover.hover( function() { $hover.showInfoMessage('', { messageElement:$msg.clone().show(), transient: false, position: { my: 'bottom left', at: 'top center', offsetTop: -7 }, dismissable: false, relativeToBody: true }); }, function() { StackExchange.helpers.removeMessages(); } ); }); }); May 23 at 11:10

• Comments are not for extended discussion; this good conversation about whether or not this question really is a duplicate has been moved to its own chat. Please, if intending to vote on this question's status, familiarize yourself with and contribute to the conversation there. – nitsua60 May 23 at 14:14
• How will your character create "25 foot long pointed Tungsten Rods" in spite of the fact things made via the spell Creation "must be no larger than a 5-foot cube"? Similarly, how do you intend to use Maleable Illusion to turn your created objects into "a 3375 ft3 cube of pure tungsten" given that malleable illusion requires you to use "the spell’s normal parameters for the illusion" (PHB, p. 118)? – Gandalfmeansme May 23 at 22:09
• (Naturally, none of my concerns above invalidate the underlying question [how to manage damage from heavy objects moving fast] but it's a confusing aspect of the current question). – Gandalfmeansme May 23 at 23:28
• This also begs the question how you will create Tungsten at all. The text for Creation states "the object must be of a form and material that you have seen before" (PHB, p. 229). Tungsten as a metal (rather than a crystal or an acid) was discovered (and indeed, created) in 1783. Assuming that your campaign is based on medieval periods, tungsten (as a solid metal) probably wouldn't exist yet. – Gandalfmeansme May 24 at 0:42
• @Gandalfmeansme If you read my description the spell is being cast at 7th level - which means the cube can have a square area with up to 15ft sides. A cube with 15ft sides is actually 30ft from furthest point to point (using pythagorean theorem), so a 25ft pole is completely reasonable. A cube with 15ft sides is 3375 ft3 (15ft*15ft*15ft = 3375ft3). – Whambulance May 24 at 6:19

# There aren't really any rules

There are no specific rules for falling objects in 5e, which comes back to D&D (5e) not doing physics well. It is left to the DM's intuition.

But that doesn't mean we have nothing to go on. The rules/guidelines on page 249 on improvising damage provide a rough scale for damage (number of d10s) for different kinds of 'events'. So let's try to see the one which is closest to your scenario.

The 'naive' answer here might be that a massive tungsten cylinder is equivalent to a flying fortress (apparently a more likely occurrence), the recommended damage for which is 18d10.

However the scenario you described is actually closer to Rods from God1 which is, in short, dropping a massive tungsten rod from orbit producing the effect of a nuclear detonation without the bothersome irradiation afterwards. This might be considerable worse than a mere flying fortress. The last item on the improvised damage table (for 24d10) reads

Tumbling into a vortex of fire on the Elemental Plane of Fire, being crushed in the jaws of a godlike creature or a moon-sized monster

and if you feel being at the center of a nuclear-like explosion is equivalent to one of those descriptions, use that damage. If you feel it is worse, the follow up questions might be "how many dice do you have?", "how much time do you want to spend rolling them?", and "is the outcome going to be anything other than they are dead?".

Of course this is only the damage magnitude of the effect. The radius of effect and whether creatures (bbeg and key minions) are affected is going to be up to you (the DM) and maybe in particular how much you are willing to let creative solutions solve/bypass challenges. There is no set right way to solve this, but personally I would let this "solve" the problem of all the minions (meaning they don't have to be fought), leaving only the 'final boss-fight' against the bbeg (assuming this is your story structure).2 The main argument I have for doing so (in addition to "I had planned this fight to be really cool") comes down to having all in the party participate: If the powers (i.e. spells) of only one party member solves the problem/conflict, it means the other members aren't contributing. This can very easily lead to them feeling redundant or useless, meaning they aren't having fun. And the DMs most important job is to try to make everyone have fun.

1: We are here using the real world idea, not the fancy sticks handed out by celestial beings as is more common in D&D.

2: We are leaving the bbeg alive under arguments that their stronghold is sufficiently fortified, quite possibly magically. Remember that bad guys tend to have defences that often parallel or outperform the good guys attacks in heroic storytelling.

• I still think this is a dupe, but you could include a reference to siege weapons from the dmg. – NautArch May 23 at 12:18
• There's also consideration of WMDs. If you can do this, so can others. Why hasn't it been done? WHy isn't this a constant threat? And...how do they even know what tungsten is :P But I also think you should consider adding this as an answer to this question. – NautArch May 23 at 13:42
• @NautArch As for why this isn't done often, it requires a 7th level slot (minimum 5th level, but with severly reduced effects), and to be quite a distance above the ground for a minute straight (required to concentrate on casting the spell). Tungsten itself was discovered (in the real world) in 1783, so I think while it'd be somewhat dependent on the setting, its reasonable to have Tungsten discovered – Whambulance May 23 at 13:49
• @JackBrooker I'm not sure if it'll move the needle on your answer, but if magic/magic users are uncommon in your world then that may be a pertinent piece of knowledge. – NautArch May 23 at 13:57
• @NautArch Are you referring to me saying that requiring a 7th/5th level slot would mean it isn't that common? I would have assumed that 9th level Wizards and up were fairly uncommon in most worlds? – Whambulance May 23 at 14:18