Delay Spell( Player's Guide to Faerûn, p. 37)
You can cast spells that take effect after a short delay of your choosing.
Any other metamagic feat,
A delayed spell doesn't activate until 1 to 5 rounds after you fi nish casting it. You determine the delay when you fi nish casting the spell, and it cannot be changed once set. The spell activates just before your turn on the round you designate. Only personal or touch range spells and those with areas can be affected by this feat. Any decisions you would normally make about the spell (including attack rolls, designating targets, or determining or shaping an area) must be made when the spell is cast. Any effects resolved by the subject (including saving throws) are determined when the spell triggers. If conditions change between casting and triggering in such a fashion as to make the spell impossible (for example, if the target you designate leaves the spell's area or moves out of range before it goes off), the spell fails. A d elayed s pell m ay b e d ispelled n orm ally d uring t he d elay period, and spells such as detect magic can detect it normally in the area or on the target. A delayed spell uses up a slot three levels higher than the spell's actual level.