Create Paradox

When paradox is cast, the caster may alter a minor event from his past that may affect the present. Such an event could be exchanging one memorized spell for a more useful one, having bought a cask of ale instead of a keg of oil, or deciding that, instead of insulting the Orcs chieftain (who has been harboring a grudge, and now the characters need his help), the heroes insulted their finest warrior. 

The event to be changed should not be more than three hours in duration, and it must be something that was personally done by the caster or something the caster could have influenced. (Perhaps a thief actually made the insult, and the caster uses paradox to explain it away at the expense of the orc warrior.) The caster can change an event as far back as one day per spell level. It is the Dungeon Master's call as to how the change proceeds forward, if at all. Often, things will not work out as neatly as the caster might hope.