by Mike Shea on 25 February 2013
The Lair Assault organized play program brought a more competitive form to our traditional D&D 4th Edition games. Lair Assaults put PCs into challenging and focused scenarios, giving them a main goal, some constraints, and a heck of a challenge. Today we're going to look at some of the elements and design concepts behind building a lair assault so you might bring the same sort of constrained and focused challenge to your own 4e game.
A good lair assault style adventure focuses around a single theme. In the critically acclaimed Lair Assault Kill the Wizard, we had a theme already in mind: drow assassins hunt down a wizard who is building a drow-destroying creation of some sort (Spoiler: it's a big drow-eating pacman construct). When building your own lair assault, find a clear overall theme for the scenario and reinforce it throughout your design with goals, environments, new game elements, and the monsters you select.
Similar to the concepts of a Combat Out Lair Assaults all have a clear and focused goal. Building an adventure or encounter in the style of a lair assault means setting one of these clear goals. Such goals might include thefts or heists, the specific destruction of a single creature, solving a particular puzzle, activating four beacons of power, or any other in-game mechanical goal. Killing all of the monsters is rarely the primary goal for a focused adventure like this. Instead, pick a specific goal the PCs can achieve while fighting off the hordes of monsters you plan to throw at them.
Lair Assaults have a clearly focused battle areas. You can easily simulate this focused area with the right poster map. In particular, the Haunted Temple, Vaults of the Underdark, or Shattered Keep map packs include some excellent poster maps upon which you can focus your scenarios.
These battle maps should have lots of powerful environmental effects both dangerous and advantageous to the PCs. The mixture of good environmental effects, a clear theme, and a focused mechanical end-state add new and interesting variables to your 4e game.
A focused scenario like this gives you some room to add new gameplay elements. These might take the form of puzzles or some other random elements. In the Kill the Wizard lair assault (written by yours truly), players could accomplish achievements by betraying fellow drow. In Attack of the Tyrantclaw, players could create their own defensive elements to fight on their behalf. Try adding in some new gameplay elements to the game that reinforce the feel you're shooting for with the overall scenario. Try to keep these elements simple, however, so it doesn't make a long battle even longer.
Lair assaults are a great way to be a dick with your overall environmental effects. You can put in some excellent zone-wide effects that always take place. Add damaging effects to teleports or critical hits. Hinder healing effects. Change how marking targets works. Again, you don't want to be too brutal with these effects since entire character concepts might fall apart. Don't negate their powerful abilities, challenge them!
When it comes to encounter balance, take the gloves off and go crazy. You can throw two or even three waves of monsters at PCs, if they are a high enough level. Don't worry too much about perfectly balanced groups of monsters. Send them in as it makes sense. You might not even separate the battles and just run one long initiative with some environmental effects or options for resetting encounter powers.
Because of the tactical nature of a scenario like this, expect the battle to take significantly longer than you might expect. It's not unheard of for lair assaults to take three or four hours for one or two encounters. Give your game some room so you don't have to rush people through it. Expect things to take a while and you'll all have a lot more fun during the game.
A focused scenario like this doesn't have to be a stand alone event. You can easily fit events like this into your ongoing campaigns for a more board-game-style challenge in the middle of your longer campaign. If you're making it very challenging, have a good plan should the party completely wipe out. You don't want to wreck your game just because a battle like this went south for the PCs.
Scenarios like this are your chance to break the rules of 4e D&D. This isn't for inexperienced DMs, however. You'll want to have a good feeling for how encounter balance and character power works in D&D so you know what rules you can break. Once you've designed the scenario, sit back, give them hell, and have some fun.