by Mike Mearls

Welcome to "Setting the Stage," a series of articles that helps you build interesting and fun encounters for your campaign. "Setting the Stage" is written with The Book of Iron Might in mind, but you don't need to own it to make use of this series. The first installment looks at the most basic types of encounter dressing you can use—cover and blocking terrain. Later installments introduce new rules and ideas for exotic locales.

The Book of Iron Might introduces innovative new systems for high-octane battles in your roleplaying sessions. The maneuver system in Chapter One allows you to translate almost any combat move into its game mechanics effects, while the stunt rules in Chapter Four illustrate how you can use simple skill checks to model fearless deeds of derring-do.

Game rules exist only within the context of your campaign. They only come to life when you unroll your battle mat or assemble your Tact-Tiles, bust out the chips and soda, and start rolling dice. This article looks at the context in which you can use maneuvers and stunts. It provides new rules and guidelines for designing encounters where the terrain provides a natural jumping off point for a stunt. A rickety stone wall just begs for a beefy fighter to knock it over and scatter a gang of thugs. An old oil lantern swings from a cave's ceiling, providing the perfect target for an archer who wants to knock it from its hook and send it crashing onto a troll.

The terrain and conditions at an encounter area can open up a wide array of new options and decisions for both the PCs and their foes. If you build an interesting area, your encounters become more memorable and the players grow more engaged in the game. They must take in your description of the environs, visualize it, and think about how they can turn it to their advantage. This process becomes doubly important if you demonstrate that their enemies can and will do the same.

At their heart, terrain features are like toys left scattered about the encounter area. With a little imagination and motivation, the characters can have a lot of fun with them. The generic terrain traits given here are meant to illustrate the mechanics behind a terrain feature. Use them to consider how you want a part of the scenery to interact with the encounter.

Cover

Cover is a good way to make one portion of an encounter area important or difficult to approach. If one side has cover and the other doesn't, the exposed combatants are at a serious disadvantage. They must either rush their opponents and turn the cover into a non-factor, or find a defensible position of their own. Cover usually has one of two effects. It can turn an encounter into a mad rush, as both sides take cover or one makes a crazed charge at a dug-in position, or it can slow things down. In the latter case, if both sides have cover they might be content to sit tight and rely on spells or ranged attacks. If the party has a lot of melee-focused characters, the players might grow bored, or the encounter could take a while.

Cover is best used in conjunction with other terrain features. Since it's a natural attractor for the characters, you can set up situations where the party must attempt a stunt or move through challenging terrain to reach the cover. A small pile of boulders that can shield the PCs from an archmage's magic missiles might be accessible only by a rickety old bridge. The orc archers fire at the player characters from behind a stone wall, leading the party's monk to pole vault over the barrier with his staff.

Most maneuver effects involving cover focus on ways to remove the benefit it offers to a foe. Sniping Shot can ignore cover, while the Forced Movement and Knockback melee maneuver effects can dislodge an opponent. Most stunts that the PCs use in this situation involve moving around or through cover. Try to include terrain features that encourage such actions. The stone wall that the goblins hide behind is old and crumbling, leaving it ripe for destruction. A rogue could anchor his grappling hook on a wooden beam and swing over the piled crates that the assassin squad hides behind.

Here's a quick checklist of issues to consider when adding cover to the mix:

Samples and Ideas

Here are a few ideas for using cover in an encounter.

The monsters take cover behind something that could be destroyed, such as a rickety brick wall or bundles of hay that could go up in flames. If the PCs destroy it, using it either a maneuver or a stunt, they take out the cover and hurt their enemies.
The encounter area is studded with cover, forcing the characters to move from one spot to the next. Anyone stuck in the open might suffer a breath weapon or spell attack.

The cover moves around. Aboard a storm-tossed ship, crates slide back and forth. A spellcaster might be safe one moment, only to find himself open the next. The crates could bull rush anyone caught in their path.

The characters can make their own cover by shooting stalactites from a cavern's ceiling. If the monsters use this tactic, they might lure the PCs into the open before springing their plan.

Barriers

Many DMs like to think of dungeon maps as flow charts. They chart out all the possible pathways that a party can take, making it much easier to anticipate the characters' moves. Barriers, or any obstacle that makes movement difficult or impossible, work in much the same way. You can use barriers to help channel the characters into certain areas during an encounter, or you can use them to present PCs with a limited number of options. Barriers are great fodder for stunts and maneuvers, since the characters usually can gain a tremendous tactical advantage if they can circumvent anything that blocks their movement.
Barriers work best at low levels, as parties of 7th level or higher tend to have spells and magic items that allow them to fly, levitate, teleport, and otherwise move from point A to point B without walking. This is an important point to remember when creating encounters for high-level parties. Most PCs have excellent maneuverability. Don't rely on a barrier or other terrain feature to slow them down.

Barriers come in a wide array of forms. A simple dungeon wall prevents movement, as does a deep, rushing river. Other "barriers" channel the characters along certain paths. A tunnel through a wall forces the PCs to move along its path if they lack magical means to move through the stone.

A barrier might provide a clear path, but moving through it comes at a price. A river of lava could kill a PC who tries to move across it without protection, while a spell such as spike stones can have a similar effect. Remember, a barrier is anything that inhibits or prohibits movement. Use your imagination to come up with inventive ones.

The most daunting barriers lack symmetry. In other words, they prevent one side from moving while allowing the other to move without penalty. A river of lava stops a party of adventurers in their tracks, but a swarm of fire elementals can move through it with ease. The characters must move along a ledge set into a cliff face, but the harpies swooping in to attack can soar above, behind, and below them. In such cases, the PCs' enemies can move to attack then retreat for healing. They can also rain spells and missile fire upon the party without fear of the party's barbarians or fighters. In terms of scenario design, this neutralizes the party's melee attacks. Just keep in mind that an encounter that relies solely on ranged fire and spells might be dull or it could take a long time, unless the player characters have the option to rush ahead and escape their enemies.

Maneuvers give a character (or monster!) the chance to turn impassable terrain into a deathtrap. Knockback becomes a deadly effect if you use it to send a hobgoblin off the edge of a 100-foot cliff. A troll might bull rush a dwarf into quicksand. A white dragon could use an Area Attack to slam the thin ice that the party stands upon, smashing through it to plunge them into the water. Maneuvers in these situations work best when they take advantage of the terrain. They don't have to inflict extra damage to prove useful. A fighter without ranks in the Climb skill is as good as out of the fight if an ogre pushes him into a pit.

Since barriers channel the characters along certain paths, you can use that knowledge to plan ambushes and other tactics. If the PCs' opponents are intelligent enough to make plans, they should be ready for the characters as they move through the area. Snipers might ready attacks to fire arrows at a PC who emerges from a tunnel. Rogues or monsters with ranks in Hide might station themselves for an ambush or to attack the party from behind once battle is joined. Just like with your dungeon map, chart out likely pathways and allow the monsters to plan their tactics.

Stunts allow the characters to turn such plans on their heads. Skills such as Balance, Tumble, Climb, and Jump can allow the PCs to move through terrain that should otherwise prove impassable. The barbarian leaps over the orcs' trenches, allowing him to attack their king. A monk uses a vertical run to go up a wall, run along its length, and leap down upon the wizard who thought he had a safe firing platform. If the monsters planned on the characters' moving along a predictable path, these stunts can give the PCs a tremendous reward. With the villains' plans ruined, the characters are in a good position for victory. This reward shows the players that stunts can help them, giving them a great incentive to keep trying them. If you want stunts to play a big part in your game, this is a good opportunity to promote them.

Here's a quick checklist of issues to consider when adding barriers to the scene of a battle:

Samples and Ideas

Here are a few ideas to get you thinking about how to design and use barriers in encounters.

A barrier can take someone out of the fight for a few rounds without killing or injuring her. A deep pit, water, or quicksand can trap a character until she gets free.

Open space can be a difficult barrier if the characters cannot fly. Crevasses, cliff faces, and other areas keep lines of sight open while restricting movement.

Keep the holes and paths through difficult terrain at the appropriate size for the encounter. Large creatures may have to squeeze to move through narrow areas. A narrow pathway favors whichever side is outnumbered, since it can force the larger group to attack one or two at a time. On the other hand, a narrow pathway reduces the party's options.

Barriers do not have to be static. Gates can open and close, while a gem or some other focus might control the magic that allows a fiery wall to burn the characters. If the party destroys this focus, the wall collapses.

Keep in mind some of the advice given for cover. Try to keep one or two options open for stunts. The party's barbarian might knock over a stone column to create a bridge over a lava stream. A monk might jump on the back of a wyvern when it swoops by to attack the cliff ledge that the party must navigate.

For more about maneuvers, see The Book of Iron Might free preview. Also check out Part Two of this article.