Now that you know what the map looks like, how to handle long- and short-range battles, and how the figures interact on the map, it's time to discuss the set-up and presentation of a fight. What effect does surprise have? Where do terrain features go? Who sets up their figures where?
Surprise[]
Before a battle begins, one or both sides may have to check for surprise. The Dungeon Master has the final word on whether or not a surprise check applies. There are situations in which one side may have to make a surprise check but their opponents don't—for example, an ambush or a nighttime encounter with enemies carrying bright lights. Surprise conditions and modifiers are discussed extensively in the DMG and the PHB (Chapter 11: Encounters for both). (Encounters (PHB) & Encounters (DMG))
The surprise check is a d10 roll, modified for the surrounding conditions and any special preparations one party or the other makes. Normally, a group is surprised on a roll of 1, 2, or 3. The surprisers get a free round of attacks, movement, or spells against the surprised members of the other group.
Encounter Distance[]
The distance between two groups is an important part of setting up the battle. The terrain and weather have a great effect on encounter distance; even an eagle-eyed character will have a hard time spotting his enemies in a dense fog or pitch-black night.
The DM can simply assign an encounter distance based on his estimation of the situation, or he can roll on the table below. In many cases, the range of the encounter is obvious; if a party of heroes kicks down a dungeon door and storms a guardroom, it stands to reason that the gnoll warriors are somewhere in that room.
Situation | Range (melee scale) |
---|---|
Both groups surprised | 1d4 squares |
One group surprised | 1d6 squares |
No surprise: | |
Smoke or heavy fog | 1d8 squares |
Jungle/dense forest | 2d10 squares |
Light forest | 4d6 squares |
Scrub/brush/bush | 4d12 squares |
Grassland/field | 10d6 squares |
Dungeon/night | Limit of vision |
No cover | Long missile range |
Note that dungeon or night encounters refer to the vision limits of whoever can see the farthest. If a party of heroes equipped with lanterns can see 30 feet in a dark forest, a hunting party of orcs that can see 60 feet may try to open the battle with a volley of arrow fire out of the darkness.
If a situation arises where there is no real cover or the enemy's approach is detected hundreds of yards away, the encounter should be set up at the maximum range of the longest-range missile weapon in the fight. In this case, it will probably be necessary to begin the battle in missile scale and move to melee scale when the groups close.
Set-up[]
The last step before starting the fight is setting up the battlefield and the location of the combatants. The DM should first arrange the battlefield; if the fight is taking place in a room inside a dungeon, the DM notes the room's size, shape, and interesting contents before placing any creatures in it. Chapter Three describes battlefields of all kinds in great detail.
If one side has spotted the other without being seen, or has surprised the other group, they can make their opponents set up first and then place their own combatants to take advantage of the situation. (They still have to observe the encounter distance dictated by the DM, though.)
If neither side is surprised, or if other special circumstances exist, the DM can dictate the positions of all characters and monsters at the beginning of the battle. The PCs should be set up in their normal marching order, with any adjustments the DM deems appropriate. Someone had to open the door to the guardroom, after all. The monsters are placed by the DM as she sees fit.
If the DM knows something the players don't, there's no reason she can't keep some figures off the map until the players have reason to spot them. If there's a giant spider on the ceiling and no one looks up, the DM should feel free to spring a fiendish surprise when a character walks under it.