Creating a magic trap, Explosive Runes & Dispel Magic

[Kerilstrasz]

I want to create a simple magic trap.
Although, there are many steps i m unfamiliar, thus i come here for your help & guidance.

1st.
Explosive Runes (http://www.d20srd.org/srd/spells/explosiveRunes.htm) deals damage to the following: Anyone[...], Creatures & the item the runes written on.
So i deduce that every other inanimate Object in the vicinity of the blast is unaffected, correct???

2nd
I want to create a magic trap with proximity trigger. Can i , somehow, have it ignore creatures that bare my arcane mark? or they are specified to be ignored when i create the trap???

Now..
if 1 is correct & 2 can be done, my idea is:
a lightweight object (so it can be manipulated with mage hand) like a paperclip; which will be the proximity trap, casts area dispel magic.
i fix several papers full of Explosive Runes in it & mage hand it near some monsters(or place it at a spot that they will pass). The paperclip triggers when they get in range(maybe add delay of a couple of seconds) and casts dispel magic on the papers. Expl.Runes casting will be on higher CL than dispel magic, so it fails to dispel them and they detonate. BOOM!

Is my idea correct? Do you have any suggestions that could make it better?

3rd question.
How many castings of explosive Runes i can have on a single page?

Thank you all for you time.

[unseenmage]

I'm currently engaged in trying to figure similar things out for a character of my own.

Some stuff I've found:
- Illumians from Races of Destiny are immune to rune/glyph/symbol named traps of a CL less than their own CL.
- Glyph Seals from Magic Item Compendium are awesome.
- Craft Contingent Spell from Complete Arcane is potentially also awesome when combined with Create Crawling Claw from Monstrous Compendium: Monsters of Faerun and/or Thrallherd from Expanded Psionic Handbook. Make disposable minions, then apply contingent spells that will persist even after they die. Sounds like a potentially cool trap to me. :smallbiggrin:
- Unseen Servant (and his bestest friend Unseen Crafter) can be used to set off traps from afar.
- Invisible Spell metamagic from Cityscape and the Create Trap spell from Races of the Dragon is hilarious (http://www.minmaxboards.com/index.php?topic=4571.msg77861#msg77861).

Hope some part of that's useful.