Ideas for remote controlled spell completion, item...

[NevinPL]

...so you can be in a place A, and make a far away place B burst with Fireball, or Cloudkill.
Something more "straightforward" than dominated flunky, with Shalantha's Delicate Disk, and Sending Stone.

[Surpriser]

Ring Gates (Core, 40k) come to mind. You still have to get the other ring to the destination, but that should be doable. It specifically calls out casting spells through the rings as one possible use case.

[Jack_Simth]

Ring Gates (Core, 40k) come to mind. You still have to get the other ring to the destination, but that should be doable. It specifically calls out casting spells through the rings as one possible use case.
There's also the magic device trap (http://www.d20srd.org/srd/traps.htm#magicDeviceTrapCost) rules. Make the trigger use Detect Scrying, and you can set it off with a scrying sensor from, say, Clairaudience / Clairvoyance.

[Flickerdart]

Using a magic trap is an excellent idea, but rather than making it trigger off a spell, make it trigger off a spell being dismissed or altered. Permanent (D) spells are perfect for this - you could, for instance, create a permanent image and then cause the trap to "see" the trigger condition any time you wanted, or dismiss blindness/deafness from a homunculus-type servant to let it know that it needs to act.

[nedz]

Explosive Runes
Read from a distance with Scry or Clairvoyance

[NevinPL]

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Good idea, although I would prefer something less costly.


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Too convoluted, and time\XP consuming.


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Niiice.