Spellcasting traps (literal)

[Lanson]

So I was sitting at work yesterday thinking about a character I'm going to be playing as, and was wondering, when a magic trap is activated, does it take the same amount of time to cast a spell as a caster, or does it simply release a stored spell, totally ignoring action economy?

I was planning to create a magically trapped shoe insole with an automatic reset and touch trigger that would cast true strike on me whenever I touched it, being always as my foot would be constantly in contact. If the item ignores action economy and releases the spell as a non-action, would it recast the spell as soon as true strike was consumed by me attacking, and would I be getting a +20 on every strike in my iterative attacks?

[BowStreetRunner]

While I believe there are far more competent playground members to answer your question directly, let me just say that you should make sure your DM does not have any heavy objects close at hand when you spring this on him.

[subject42]

Be careful with this line of reasoning. Down this path lies the Tippyverse, and the Tippyverse revels in madness.

[pyrese]

Yes, this would work. However, the cost to create it would be astronomical: It falls under the same guidelines as a ring of invisibility. IIRC, the ring is 2000 gp according to the guidelines for creating magic items in the DMG. However, they warn that those guidelines don't always apply and that ring, when listed as a specific magic item, has a value of 20,000 gp.

I imagine an item giving you +20 on all attacks should cost well in excess of what any character who would care about such a bonus could reasonably obtain.

[Lanson]

Granted, Pyrese, however it would technically be an unslotted item. Being a trap, and not a foot slot item means it wouldn't interfere with my Boots of Haste (or whatever I may use) meaning it would still be useful at all levels of play.
Technically speaking, it has use for all characters of all types. No more needing to twinspell with a truestrike attached to bring down the BBEG. No more missing your Sneak Attacks. So I see no drawback to it, no matter what it may cost, though I fully agree that it is rather expensive and will come into play later in the game once hit modifiers are very easy to come by.

[Mutazoia]

So I was sitting at work yesterday thinking about a character I'm going to be playing as, and was wondering, when a magic trap is activated, does it take the same amount of time to cast a spell as a caster, or does it simply release a stored spell, totally ignoring action economy?

I was planning to create a magically trapped shoe insole with an automatic reset and touch trigger that would cast true strike on me whenever I touched it, being always as my foot would be constantly in contact. If the item ignores action economy and releases the spell as a non-action, would it recast the spell as soon as true strike was consumed by me attacking, and would I be getting a +20 on every strike in my iterative attacks?

Depends on what you use to create your item. Things like Explosive Runes simply release the stored up magic instantly upon triggering. However, depending on your level you could simply make use of a Contingency Spell to cast True Strike when ever you make a specific movement, such as crossing your toes or some thing. Since crossing your toes would be a free action you could theoretically do that at the beginning of every action and trigger the contingency. You could go for the super munchkin trigger of "every time I swing my sword."

HOWEVER True Strike only covers 1 attack per round, so iterative's would not be covered by true strike. Anything that would break this rule and allow True Strike to be used on iterative's would have to pass DM clearance. Who know's the DM may allow you to trigger the contingency before each iterative with the above trigger....no harm in asking.

EDIT: Plus having it as a contingency spell and not on an item means you can't loose it/have it destroyed/stolen...

[Psyren]

True Strike is Personal so I'm not certain you can get a trap (or any other object) to cast it on you.

[Slipperychicken]

True Strike is Personal so I'm not certain you can get a trap (or any other object) to cast it on you.

It would, however, cause an attack-roll-based trap to be far more accurate.

[Lanson]

Ah, I did not catch the personal tag, looks like it's back to the drawing board

[Mutazoia]

Ah, I did not catch the personal tag, looks like it's back to the drawing board

Again...Contingency....it's cheaper....