What spell level should this be...

[Another_Poet]

An illusion spell that creates illusions that are not seen by normal eyes, but are seen by Trueseeing. Thus fooling clever mages who think they've just found something invisible. In all other regards it works like Silent Image.

Thoughts?

[Cyanic]

Around 5 or 6 sounds right, depending of course on the specifics of it.

[Latronis]

Defeating truesight is kinda odd given the flavour of trueseeing.

It's fairly specific in application, but as a general rule i find something that beats something else should be higher in level.

[Edwin]

It's interesting. Not particularly powerful, so I'm not sure I would say 5th or 6th.

Maybe make it the level of the original spell, for example Silent Image, +2 spell levels.

It's got useful but very specific applications.

[Nero24200]

It seems a bit odd for it to beat true seeing, though on the other hand, a spell which creates an invisable object achevies the same effect, so I'd be willing to rule that the object occupies space and can be interacted with, but can be shaped to look threatining (so a true-seeing mage would expend resources to destory it).

[Baron Corm]

I wouldn't allow this spell. Where's the perfect true seeing spell which defeats even this? It's just circular. Before you say that since it beats only true sight and not regular sight it might be ok, consider what happens when you cast one of these onto a quickened major image. It requires two spell slots, but it defeats everything, for three rounds. If you can get something else to concentrate on one of the spells for you (I think spirit shaman, incantatrix, and possibly others can do this), or just work with another spellcaster, it can work for longer.

[Another_Poet]

I can't say I really disagree. It was mostly a passing thought.

What if it allowed a Will Save to anyone who sees it (i.e. anyone who true-sees it)? That would make it somewhat easier to defeat than a normal illusion where you have to interact with it first.

[Zeta Kai]

I'd allow this as a 7th-level arcane spell (6th-level for Bards).