Is this runecaster feat balanced?

Question

This feat is intended to allow characters to store a spell in a rune (like you see in many dungeons) with activation conditions. It is intended to scale with the party as the party gets better spells. I want it to be mostly balanced and user friendly. My concern is that it may have some unintended exploits.

Rune Caster

Prerequisites: ability to cast at least one spell of 1st level or higher

When you take this feat you can imbue your spells into a rune by casting the spell as a rune, this means that you must have the object you want to put the rune on within reach for the whole duration of the casting the casting time is also affected depending on the type of rune you are storing it in.

Type of rune

There are a 3 types of rune that a spell can be stored in:

1. Chalk

2. Carved

3. Chiseled

Each type has a different effect alongside the spell it contains

1. Chalk

   • You must have chalk to make this rune

   • Chalk runes will rub of if they are treated badly or stored

   • Chalk runes add 10 mins to the casting time

2. Carved

   • You must have proficiency with woodcarving tools and woodcarving tools within reach for the duration of the casting in order to make this rune

   • This rune can only be made on a wooden surface

   • This rune adds 30 mins to the casting time

3. Chiseled

   • You must have proficiency with masons tools and masons tools within reach for the duration of the casting in order to make this rune

   • This rune can only be crafted on stone surfaces

   • This rune adds 1 hour to the casting time

Triggers

When making a rune you may choose the trigger conditions from the following list:

• Touch

• Touch by [specify creature(s)]

• Touch and command word spoken

• Touch by [specify creature(s)] and command word spoken

When defining creatures that can activate the rune you may be as specific or general as you want. The DM interprets exactly what you say when deciding if the rune activates in a situation.

Ranges

When you store a spell in a rune the range can be affected, for example a range of touch becomes a range of self.

Casting time

When you store a spell in a rune there is no casting time, instead it uses the use item action (not the one free use item action per turn) to activate a rune.

Answer 1

As it stands it is extremely overpowered

As Dale M states this allows magic users to create unlimited spell scrolls during downtime with no real costs.

The closest parallel is the Glyph of Warding which is a third level spell. Though there are some restrictions on this compared to the full spell it effectively allows a level 3 spell at will. Needless to say that is extremely overpowered for a feat.

It's also very complicated. 3 kinds of runes with different requiements and casting time, this is more complex than most feats in source materials.

Suggested Changes

Limited Uses: Limiting it to once per short or long rest would reduce the ability to spam it. However given enough time it doesn't resolve the issues.

Limited Duration: Runes should only last (1) 24 hours or (2) until another one is created. Particularly option two would prevent misuse of this feat.

Add a material cost: Add some kind of material cost to the feat, say 10gp per spell level or a fixed 50gp.

Simplify it: I would suggest simplifying the feat. It is much more complex than most feats, reduce it to a single kind of rune and a one hour casting time.

Answer 2

This is very overpowered

It effectively allows the player to create unlimited spell scrolls by another name.

Or, it looks a bit like a Glyph of Warding (which uses up two spell slots) but way more useful because its portable.

Answer 3

This kind of sounds like an alternate description of a spell scroll to me. I'd suggest using the rules text for the spell scroll and the given rules for how to craft them from Xanathar's Guide to Everything (p.133), and then have the feat modify those rules in some way. For example, a rune is a spell scroll that only you can use, you can only maintain one at a time, and the listed time to craft it is reduced from days to hours, or weeks to days.