Fixing Things in Play (DMG)

Sometimes, for all the good intentions of the DM, encounters don't work out right. Correcting problems in play can be difficult, but there are times when it's unavoidable. Here are some tricks you can use.
==The Encounter is Too Difficult==
The DM has accidentally pitted his player characters against a group of creatures too powerful for them, so much so that the player characters are doomed. To fix things, the DM can have the monsters flee in inexplicable panic; secretly lower their hit points; allow the player characters to hit or inflict more damage than they really should; have the monsters miss on attacks when they actually hit; have the creatures make grievous mistakes in strategy (like ignoring the thief moving in to strike from behind).
==The Encounter Gave Away Too Much Treasure==
Sometimes the DM discovers his random encounters gave away too much treasure. In this case, he can have more monsters of the same or more powerful type appear on the scene. (The first group stole the treasure and these fellows want it back; or the first was carrying the tribe's treasury to safe-keeping; or the new group has been trailing the first to rob them, and now takes a very dim view of the characters getting all the loot.) In many ways this is like those westerns where everyone winds up fighting over the gold. In this case, the monsters don't want to annihilate the player characters so much as get the loot and run.
==The Encounter Was Too Easy==
As long as the treasure the characters earned was not excessive, this is not a problem. The DM can always make things tougher for them in the next encounter.