Wish

A wish spell is the true version of limited wish, an extraordinarily potent invocation of eldritch power. After casting a wish spell, the caster will be weakened considerably, requiring 2d4 days of bed rest. The only exception to this is when the wish is used for transport, healing, or resurrection of the dead. In general, the exact wording of the wish is carried out regardless of its intent, but the GM will not normally be stringent upon this point unless the wish is an attempt to overreach the spell’s power.

In the case of unreasonable wishes, the GM may decide to follow the wording of the spell precisely but pervert the intent, limit the duration of the spell to a very limited time (perhaps mere seconds!) or simply rule that the whole spell fails.

The guideline here is that wishes are granted by someone or something, which may or may not be kindly disposed to the player characters. The more greedy or selfish a wish, the greater the chance that a mischievous or actually evil power will take the opportunity to teach this upstart mortal a lesson.