Random Adventure Generator

ThemeAction/Adventure
This is the most common and straightforward sort of adventure there is. In the Action/Adventure scenario, you present your characters with a task and then confront them with obstacles to overcome in order to accomplish the task successfully.
GoalExplore a New Area
The heroes are hired or convinced to enter an unmapped area and explore it. They may be making a map; they may be trying to find someone who disappeared into this area in the past; they may be following legends that tell of treasure in the unexplored interior.
Story HookOld Friend
Another classic story hook is the Old Friend, the childhood friend of our hero, who shows up in one of several ways to drag the hero into the story.
PlotA-B-C Quest
This is an epic sort of plot. In it, the heros are given (or undertake) a task to perform: The taking of a city, the rescue of an innocent, the destruction of a monster, the creation of a magical item, the defeat of a Master Villain, etc. But the path to victory is not a simple one. To get to their goal, Event A, they find that they must first accomplish some other task -- Event B. But when they undertake the task of accomplishing Event B, they find that they must first accomplish Event C. This goes on for several encounters, until the heroes accomplish all the obstacle events which prevent them from returning to Event A, their original goal.
ClimaxChase to Ground
First, you have the Heroes Chasing the Villain. The villain, after a series of encounters with the heroes, is running to safety, to some place where he can acquire more power, or to somehwere he can accomplish some dread purpose such as assassination or mass murder. The heroes chase him, have to deal with the obstacles he leaves behind, and finally catch up to him before or just as he reaches his goal. Here, we have the final duel between the villains forces and the heroes. Second, you have the Villain Chasing the Heroes. Often, in a story like this, the heroes have found out how to defeat the villain -- such as getting to a particular temple and conducting a particular ritual. The villain chases them all through their quest, catching up to them just as they're commenciing their ritual; they must, with heroic effort, conclude the ritual while suffering his attacks. Third, you have the Master Villain's Sudden Escape Attempt. This takes place in adventures where the Master Villain's identity is unknown until the end. His identity is revealed and he makes a sudden bolt for freedom; the heroes give chase. This usually results in a dangerous foot-chase through nasty terrain -- such as across rooftops, through the dungeons, or across an active battlefield.
General SettingExotic Distant Land
The adventure will take the heroes to some fascinating and exotic distant country, where they'll have to cope with new customs, monsters unfamiliar to them, and very colorful NPC encounters; choose one of the more fascinating foreign lands from your campaign world.
Specific Setting ICatacombs
These can be catacombs beneath a living city or a ruined one; they can be long-forgotten or still in use.
Specific Setting IILost City
This is the remnant of some lost civilization or expedition, still thriving in some forgotten corner of the world. Remnants of lost civilizations can even inhabit cavern systems beneath campaign cities, preying on the above-worlders for their goods, slaves, and sacrifices.
Master VillainConqueror
This character is moving his army in to take over; that's what he lives for. He's been the enemy of your characters' nation's ruler, and has launched a full-scale invasion of your characters' favorite nation. The heroes have to beat their way through or elude his hordes of soldiers in order to get at him; better yet, they might lead their own nation's troops against his and outthink him in military fashion.
Minor Villain IMoronic Muscleman
This fellow is a huge, powerful monster of a fighter. His job is to smash anything the villain tells him to smash. He does that very well, but don't ask him to do any thinking; he has no time for such brainy stuff.
Minor Villain IISingle-Minded Soldier
This most trustworthy of villain minions is the experienced, competent, persistent soldier -- a field-trained officer who serves the villain with military precision. He is usually encountered in the field as leader of the villain's field operations. He is not encountered directly until the middle of or the latter part of the adventure; until then, the heroes encounter only his subordinates.
Ally/NeutralMerry Minstrel
This character follows the heroes in order that he might find inspiration for his song and storytelling. He can't be shut up; he sings all the day long and into the night, is a showoff before crowds, and is far too noisy for a party trying to remain unobserved.
Monster EncounterNoble Beast
With this encounter, the heroes find that they have to capture -- but not injure -- some sort of powerful, noble beast in order to accomplish their mission. For instance, to reach a mountain-top aerie, they must capture pegasi and ride them up to their enemy.
Character EncounterThief
At some point in their adventure, the heroes have a run-in with thieves.
DeathtrapStampede
Should the heroes ever cross plains or prairies, their villainous enemies may wish to stampede a herd of large animals at them. Alternatively, beasts in the forest may be stampeded by fires set by the villains; in this case, it will not be one sort of animal charging through, but a mixture of terrified forest animals, from the smallest fox-cub to the largest bear.
ChaseSpecial Terrain
You can make any chase more memorable by having it take place in a setting to which it is utterly unsuited. For instance, horse chases are fine and dramatic when they take place through the forest, out in the open plains, or along a road -- but they become diabolical when they take place inside the Royal Palace or in dangerous, labrynthine, treacherous catacombs.
Omen/ProphesyTotem Animal
If a hero has an animal which is his totem, he may see the animal engaged in a fight to the death with another animal -- one which, coincidentally, is the totem of one of the villains. How his totem defeats the other -- or is defeated by it -- gives the hero some clues as how to fight his actual opponent when the time comes.
Secret WeaknessLove
The Master Villain possesses the "weakness" of genuine affection or love -- probably for some NPC, though it could be very intriguing if the object of his affections is a player-character. The heroes can then defeat the villain by holding his loved one hostage, or proving that his loved one will be seriously harmed, betrayed, or killed if the villain keeps up with his activity.
Special ConditionTime Limit
Finally, the most obvious condition to place on an adventure is to give it a time limit. If the Master Villain is going to conclude his evil spell in only three days, and his citadel is three hard days' riding away, then the heroes are going to be on the go all throughout the adventure -- with little time to rest, plan, gather allies, or anything except get to where they're going.
Moral QuandrySaving Quandry
Finally, another classic quandry puts the heroes in the position of choosing between a grand opportunity to hurt the Master Villain -- or saving the lives of a number of individuals.
Red HerringFalse Path to the Artifact
Once again, if the heroes have had too easy a time finding the artifact capable of destroying the villain, give them trouble this way: When they get to the place where the artifact is supposed to be contained, they find the coffer or chamber or whatever empty, obviously looted by robbers, who have scrawled such remarks as "Kelrog was here!" upon the walls.
Cruel TrickMission is a Ruse
In the course of their adventuring, the heroes discover they have been tricked into performing a mission which helps the Master Villain.

Based upon tables from the Dungeon Master's Design Kit by TSR, Inc.