D&D 5E Worldbuilding: destruction and siege via Mold Earth?

[greg kaye]

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So what does 60gp of work look like in d&d? Well, its 300 unskilled laborers for one day, at 2sp each.
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Perhaps the unskilled laborers' efforts may be best channeled into loosening the earth so as to leave the druids, sorcerers, and wizards to focus on assembling it into the ramp outside the clerical stronghold.

 

[kigmatzomat]

Perhaps the unskilled laborers' efforts may be best channeled into loosening the earth so as to leave the druids, sorcerers, and wizards to focus on assembling it into the ramp outside the clerical stronghold.

Well, if they were disturbing compacted soil, that would make sense. It's not like a Motte couldn't be built of compacted soil, it just takes times & effort. Add 8" of soil, pound it until it is only 6" thick. You could run a herd of sheep across the freshly deposited dirt for 1-2 hours (sheep have an extremely high weight/foot area ratio) or have people walk around with a heavy log they thump on the ground (aka a tamper).

Plus sides of a compacted soil motte: it is resistant to Mold Earth and requires more effort from sappers.

Plus side of a loose soil motte: it is more likely to collapse on any sappers or anyone doing excavation immediately, forces them to do more effort, and your Mold Earther can collapse the pit on them. Restrained targets are easy targets.

General rule of thumb for loose/uncompacted soil is use a 3:1 cut back. Go down 5ft, pull the top back 15ft. Otherwise you need shoring. I.e. to dig a safe 10ft deep hole, it needs to be a pit 70ft across. Loose sand will collapse immediately and you have to do that amount of excavation.

Compacted soil will eventually collapse as it loosens along the disturbed edge but "eventually" might be in a month or a year.

Table on angle of repose for loose vs compacted soils:

Angle of Repose Values for Various Soil Types

structx.com

 

[TwoSix]

On the notion that you need to "see the earth" your moving. I respect that the spell does say this. However, it becomes immediately obvious that you cannot affect the area the spell specifies (a 5 ft cube) with that restriction. the spell is in internal conflict, and so a DM ruling is required.

This. If you get too pedantic about the sightlines, then realistically you could only move a molecule-thin layer of dirt from the ground at a time, as that's all you actually "see".

 

[AmandaBarbarian]

This. If you get too pedantic about the sightlines, then realistically you could only move a molecule-thin layer of dirt from the ground at a time, as that's all you actually "see".

Yeah the spell just can't work if line of sight means you need to see all of it at once, it is physically impossible to see all sides at once