Let's say you have a building site that could fit in a roughly 100 feet square. And you want to hide it without hindering workers.

Now you could use the mirage arcane spell to hide the building but, a.) the workers would not be hidden, and b.) even the workers would not see the building (which seems counter-productive).

Or, you could use Mordenkainen's private sanctum, which would hide the build site in a not at all conspicuous 100 feet square fog (insert sarcasm sign here).

With the above considered: can you use hallucinatory terrain to hide the fog, by making the original terrain there?

  • If yes, how would that work for the workers?
  • Or could you create a terrain that hides the fog and is even more inconspicuous?
  • Or am I thinking too much into that and there is a completely different approach to this?

Is it even possible to do this in D&D 5e?

  • \$\begingroup\$ Welcome! You can take the tour as an introduction to the site and check the help center if you need further guidance. Good luck and happy gaming! \$\endgroup\$
    – Sdjz
    Commented Apr 4, 2019 at 15:36
  • 3
    \$\begingroup\$ Are you looking for magical solutions only? When you say hide, can something else appear to be there, or should it look like normal unclaimed land? \$\endgroup\$
    – BlueMoon93
    Commented Apr 4, 2019 at 15:40
  • 2
    \$\begingroup\$ Why are you trying to hide it? \$\endgroup\$
    – goodguy5
    Commented Apr 4, 2019 at 15:41
  • \$\begingroup\$ @BlueMoon93 While I do not look for magical solutions only, I do look for solutions a wizard might come up with ;). And yes Something else can appear to be there, but it would be preferable if it is or at least resembles the original terrain. e.g. a ship is being repaired near a cliff and would like to hide it from people who look down from the said cliff, or a tower is erected in a valley and would not be seen from the entrances of said valley. \$\endgroup\$
    – Veronika
    Commented Apr 4, 2019 at 15:56
  • \$\begingroup\$ @goodguy5 I am trying to hide it so nearby populace, and possible monsters would not get alerted until it is done. \$\endgroup\$
    – Veronika
    Commented Apr 4, 2019 at 15:59

1 Answer 1


Multiple upcast Major Images

If you're a Wizard with 6th level slots, you can conjure up a permanent illusion with Major Image.

You create the image of an object, a creature, or some other visible phenomenon that is no larger than a 20-foot cube. The image appears at a spot that you can see within range and lasts for the Duration. It seems completely real, including sounds, smells, and temperature appropriate to the thing depicted.

You can cover your building and workers with the illusion of a mountain, large trees, or whatever else you can think of. I drew an illusory tree over a tower in construction, to give you an idea of what I mean.

enter image description here

It doesn't hinder your workers, who just need to interact once with the illusion to see through it.

Physical interaction with the image reveals it to be an Illusion, because things can pass through it. [...] If a creature discerns the Illusion for what it is, the creature can see through the image, and its other sensory qualities become faint to the creature.

Depending on how big your building is, you can cast multiple Major Images to cover everything up.

When you cast this spell using a spell slot of 6th level or higher, the spell lasts until dispelled, without requiring your Concentration.

Just find a way to prevent other on-lookers from physically interacting with the Illusion and it should be hidden from most people. Keep a few Lore Bards around to use their Bardic Inspiration Die to subtract from any nosy onlooker's Investigation Check.

  • \$\begingroup\$ Won't the workers interacting with the illusion (by being inside of it) make it clear to onlookers that it's not real? \$\endgroup\$
    – NotArch
    Commented Apr 4, 2019 at 16:18
  • \$\begingroup\$ They must be covered by the illusion. Like a big rock that keeps them and the building from the sight of anyone outside. I've added that to my introduction paragraph \$\endgroup\$
    – BlueMoon93
    Commented Apr 4, 2019 at 16:18
  • \$\begingroup\$ Gotcha - so they're deep enough inside the illusion that their movement isn't seen disrupting it? I'm not sure I'm 100% on board, but I get it. \$\endgroup\$
    – NotArch
    Commented Apr 4, 2019 at 16:25
  • \$\begingroup\$ Can you make a major image in front of an object and project on it what is behind said object? e.g like a tv screen and a camera linked? if so this could work, although it would need quite a few slots to do. \$\endgroup\$
    – Veronika
    Commented Apr 4, 2019 at 16:25
  • \$\begingroup\$ @Veronika I don't think so. You can change the look of the illusion with your action if you're within range, but it's not the same. \$\endgroup\$
    – BlueMoon93
    Commented Apr 4, 2019 at 16:30

You must log in to answer this question.

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