Magic items - when do they have ongoing effects vs spell duration limited effects?

[Rycaut]

There are a lot of items (both wondrous and rings especially) that replicate the effect of common spells and offer the ability to activate that ability at-will.

Examples would be Hats of Disguise, Ring of Invisibility or a Ring of Blinking

A helm of comprehend languages and read magic makes it pretty clear that the effect is always one.

The hat of disguise I've almost always seen used as if the duration was unlimited but does the "as with a Disguise Self spell" imply that the duration is actually only 10 mins (CL 1)?

similarly in play historically I've always see a ring of invisibility used to generate ongoing invisibility (until the wearer attacks - then it takes an action to reactivate) but does it actually only allow for a 3 min duration with each activation? (CL 3).

How would an item that grants the effects of the spell OTHER than the duration be written? (i.e. one that allows you the ongoing benefit either always active or on demand)

In play and outside of combat this can probably be hand-waved - but the limited duration makes some items like the hat of disguise less useful for long term uses (such as infiltration in a social setting that is longer than 10 mins - you would have to somehow hid your reactivation).

There are other items which are strongly implied to have a longer duration by their flavor text such as a Cap of Human Disguise (which since it has a CL of 3 even though it costs 1000gp less than the CL 1 hat of disguise would apparently if spell duration applies have a longer duration than the theoretically more powerful Hat of Disguise)

[Archaeik]

I can't say there's a hard and fast rule for this... but I'd say that most items default to continuous unless their description indicates otherwise (including the Ring of Invisibility/Blinking's "as the spell" -- note the difference that Hat of Disguise says "functions as").

Additionally, I'd use two guidelines to determine ambiguous cases

Does allowing continuous break the game in some way? (almost definitely yes in the case of RoI)

Does disallowing continuous destroy the usefulness of the item? (absolutely yes in the case of HoD)

In the event the answer to both is yes, you'll need to make a call, but I'd probably err on the side of not breaking the game.

Otherwise, I'd assume that every crafter using the "use-activated/continuous" entry would default to continuous since it's the more powerful of the options.

ps. in the case of RoI, I'd consider running it at CL5 since that's consistent with it's pricing.

[Skylancer4]

Your activation doesn't have to be loud and flashy, unless it states it does. As you've found out there are actual durations for many of the items but "effectively" they are unlimited. A standard action activation just means you pause every 8 or 9 minutes to renew the effect, and worst case scenario is where you were moving constantly so would fall behind or pull attention. If you are sitting around talking "in rounds" it wouldn't really matter. It would only draw suspicion if they were suspicious and that wasn't expected.

Basically, it means you have to use the item intelligently. But usually it doesn't really matter as intelligent use of it, effectively gets the desired result.

[wraithstrike]

If the item emulates a spell that needs to be turned on then it normally has a limited duration. Some items such as a ring of protection are always on however.

[Rycaut]

Yes. I understand all of this. (I've been playing dnd for 30+ years) my question is how precisely should you differentiate both for existing and especially for custom or new items. It seems like the language is variable and that people interpret it differently. (As I noted historically I've always seen the ring of invisibility run as a continuous item that needs to be renewed only if you break invisibility - ie attack but otherwise usable for scouting etc. a duration and requirement to renew is different than I've usually seen it run in the past.

Likewise for hats of disguise (and as I noted a cap of human disguise) I've always seen those run as also unlimited - with the interpretation that they are intended for long duration disguises not a spell duration.

Something like ring of blinking is even a case where I think the strict rules are a limited duration but that has a very real mechanical effect (since it is a very combat focused item) so getting this right is especially important.

[Skylancer4]

Rycaut wrote:

Yes. I understand all of this. (I've been playing dnd for 30+ years) my question is how precisely should you differentiate both for existing and especially for custom or new items. It seems like the language is variable and that people interpret it differently. (As I noted historically I've always seen the ring of invisibility run as a continuous item that needs to be renewed only if you break invisibility - ie attack but otherwise usable for scouting etc. a duration and requirement to renew is different than I've usually seen it run in the past.

Likewise for hats of disguise (and as I noted a cap of human disguise) I've always seen those run as also unlimited - with the interpretation that they are intended for long duration disguises not a spell duration.

Something like ring of blinking is even a case where I think the strict rules are a limited duration but that has a very real mechanical effect (since it is a very combat focused item) so getting this right is especially important.

Its like real life? Some people don't pick up the manual and read the fine print, just start using whatever it is they just got? You might not need to know all the ins and outs of said thing, its general use is often close enough to the specifics, to make it "work" functionally.

Others might not care for the rules and decide to run it differently?

The rules state there is a limitation and so there is. It is up the to GM if they want to follow the rules (barring something like PFS obviously). The reasons people don't follow the rules, are too numerous to count, so you'd have to ask each specific GM why.

[Gisher]

This FAQ might be helpful.

FAQ wrote:

When I use a magic item like ring of invisibility or hat of disguise that can be activated to gain the effects of a spell, does the wording "as the spell" also include the spell’s duration?

Yes, such items' effects have a duration, as indicated by the spell’s duration and the item’s caster level. If the item has no daily use limit, however, you can simply use the item again to reset the duration.