How can Illusory Reality be abused?

[Tetrasodium]

Lets say a player got an item that granted them limited use of Illusory Reality at low levels, how could such a thing be abused by a dedicated munchkin?

[Foxhound438]

I would be tempted to cover a giant area in ball bearings or something, but I think the most broken thing you could do is use silent image to make an illusion of a forcecage, putting you up to 12 levels ahead of curve. Even if you make the magic item only able to do it once a day, it's still a forcecage every day. That would get old fast.

[lunaticfringe]

I'm afb so I'm not sure how legit it is but Lava. You can move silent image & major image iirc so move your 5ft deep Lava flow into things.

Giant bottles of Acid or poison that you dump on things

Flows of Tar

[Easy_Lee]

"The object can't deal damage or otherwise directly harm anyone." Lava, acid, and similar are right out. And on that note, the object must be "nonmagical." So force cage is also prohibited.

You need to discuss with your DM what "directly harm" means. To my thinking, cages and similar are not direct harm. So you should be able to chain up a dragon with adamantine chains, or create an effectively impermeable adamantine globe around the party to give everyone time to heal and prepare.

[Contrast]

...limited use of Illusory Reality...

Limited how? The answer to that depends on how good this would be. I'd be slightly leery of giving people magic items which exactly replicate higher level class features.

Silent Image means they can basically summon anything they can think of for a minute from level 1 on.

[Easy_Lee]

If you want to keep it under control, specify that the real illusions have only 1HP. Players summoning bridges and similar into existence isn't a problem, but cages and walls can be.

[Specter]

Crystal.

Build a crystal tower with a tiny hole from which you can cast spells, and go crazy. Melee can't harm you (usually) and archers take a -5 penalty from cover.

[Tetrasodium]

Limited how? The answer to that depends on how good this would be. I'd be slightly leery of giving people magic items which exactly replicate higher level class features.

Silent Image means they can basically summon anything they can think of for a minute from level 1 on.

I was thinking like once per long or short rest for an object that requires the dragonmark of shadow feat (house Phiarlin/Thurranni) to activate. Going with IR per PHB118 because it already has the for 1 minute & can't deal damage or directly harm clause baked in but barring anything new it's looking like the potential for abuse is pretty minoras long as I keep the resulting illusions limited to like 5-10hp

[Scathain]

I definitely think the strength of Illusory Reality is being able to pick your own battlefield. Got an archer? Put him on top of a tower with winding staircases. Make a pit, cover it with actual leaves. The crystal thing is great idea too.

[vexedart]

Did someone say free spell components for a minute? Here's your diamond, some rubies, sapphires, and a 15' cube of gold coins. Scrooge McDuck envy.

It's real strength is in battlefield control. Line of sight ab/use. Difficult terrain. Generally making your opponents work harder for their goals.
Time out domes, and walling off the entrances/exits.

It's also great for the theatre.

[Zene]

"One inanimate non-magical object "

Hate to be the bearer of bad news. But a pit is not an object. A bunch of gems is not an object. A bunch of ball bearings is not an object. All the various liquids mentioned are not an object. A force cage is definitely not a non-magical object, although an adamantine coffin with no openings, and walls 10 inches thick might work.

I think a structure, or a curving wall that perfectly divides up the battlefield the way you want it, will probably the best in combat uses. There might be other, more creative, things to do with it, but I haven't been able to think of any

[Finieous]

It's also great for the porn theatre.

FTFY. I mean, with the example of the internet, let's be honest about what illusion magic would be used for.

Add full-sensory VR to the concept and you just might have something there.