The only stuff I've currently thought about are as noted above:
* Spells that turn creatues into other states (qswap) but that wear off after a while (qswap back again)
* Items that the party can create with spells that disappear if not used within a set time
If you wanted to make it easier for dummies like me, then I'd suggest a couple of new properties for archs might be nice
expire_delay = {delay in ticks}
on_expire = {function}
So for the spell affecting a monster, the original monster would have no
expire_delay or
on_expire properties, but the qswapped version
would -- and those properties would do a function to qswap back to the original type...?