Combat spaces and arenas

A combat space is the part of a level built for fighting. An arena is a combat space that the player usually cannot leave until the fight ends; The Level Design Book describes players who drop into one as "committed" (The Level Design Book: Encounter design). The same book defines combat design as "making game systems for physical conflict between player(s) and often AI-controlled enemies too", and notes that "Encounters are structured battles against NPCs" (The Level Design Book: Combat design).

Combat comes first in this work. The Level Design Book points out that cover depends on the game's mechanics and weapons, so the core combat design must exist before the space can be tuned (The Level Design Book: Combat design). Within those rules, layout decides how a fight plays: where players hide, what they can see, how they move around enemies and where enemies come from. Environment art decides whether players can read all of that at a glance.

#Cover

"Cover is any object or structure that blocks a sightline or shields someone from attack" (The Level Design Book: Cover). It comes in two main heights (The Level Design Book: Cover):

• Low cover. "You can shoot over or jump over waist-height tables, but taking cover requires staying down and close."
• High cover. "Tall cover protects against elevated attackers but standing / sidestepping out can expose more."

Naughty Dog's Emilia Schatz gave fixed numbers for Uncharted 4, which The Level Design Book reproduces: high cover is a "Standing head height object, 1.75 or more meters", low cover a "Standing waist height object, 1.0-1.25 meters", and anything at "0.5 meters or less" is not cover (The Level Design Book: Cover). Fixed heights let players read cover from its shape alone. See grids and metrics and affordance.

More cover is not automatically better. The Level Design Book says "Often less cover is better", because "Cover blocks sightlines, which prevents players from noticing what's happening" (The Level Design Book: Cover). Tutorials, boss fights and open spaces may work best with no cover at all (The Level Design Book: Cover).

Other cover properties to plan for (The Level Design Book: Cover):

• Angles. "Cover depends on angles": as you move around a corner, "your view angle gradually gets wider -- but so does your possible exposure", what soldiers call "slicing the pie".
• Destructible cover. "breakables give temporary semi-hard cover", as in F.E.A.R. and Dark Souls.
• Soft cover. Bushes may hide players from NPCs but not from other players; some objects stop bullets but not sight.

#Sightlines

Every cover object is also a sightline decision. Long sightlines favour ranged attacks and give players information; short ones create close fights and surprises. The Level Design Book's warning that cover "prevents players from noticing what's happening" is the same trade-off seen from the other side (The Level Design Book: Cover).

#Flanking routes and loops

A flanking route lets players or enemies reach the side or back of an opponent's cover. The Level Design Book notes that directional cover "leaves blind spots for attackers to flank", which suits a front line (The Level Design Book: Cover). Enemies can use the same idea: one way to open an encounter is to "hide or spawn more enemies around the corner, and bring in these reinforcements when the fight begins" (The Level Design Book: Encounter design).

Loops matter as much as flanks. In id Software's account of DOOM (2016)'s Lazarus Labs, the medical lab's flow felt wrong until creative director Hugo Martin connected two hallway dead ends with portals to form a loop (PlayStation Blog: Classic levels deconstructed: the beautiful…). Dead ends stop movement; loops let players keep circling while they fight.

#Verticality

"Elevation gives a stronger height advantage depending on angle of attack" (The Level Design Book: Cover). Height changes how a fight feels: clearing enemies from a trench can feel good, but being pinned by a sniper or turret above usually feels bad (The Level Design Book: Cover). A high point before the fight also gives players information; The Level Design Book's third way to start an encounter uses a "vista (high vantage point)" to observe enemies first (The Level Design Book: Encounter design). See prospect and refuge.

#Arena layout and entry

Players learn to read arenas. The Level Design Book notes that an empty room "structured like an arena" may read as a trap to experienced players, and calls the problem of entering a fight "the door problem of combat design" (The Level Design Book: Encounter design). It describes three ways to start an encounter (The Level Design Book: Encounter design):

1. Reinforcements. Hide or spawn more enemies around a corner and bring them in when the fight starts.
2. A threshold. Trigger enemies once the player passes "some sort of midfield threshold".
3. A vista and a one-way entrance. Let players read the layout from above; then "once the player drops down into the arena, they are committed", sometimes with an "airlock door closing behind them".

The Level Design Book's own test-arena note suggests starting with an "open area and/or 3 lane" layout (The Level Design Book: Combat design). Lanes give predictable routes; open areas give freedom but make enemy behaviour harder to control.

#DOOM's arenas

id Software's DOOM (2016) is the best-documented example of building arenas around movement rather than cover. At GDC 2018, Kurt Loudy and Jake Campbell described its "push forward combat", which came from removing "regenerating health, reloading and cover", so that players get what they need from enemies (Game Developer: Video: The combat design of DOOM; YouTube: Embracing Push Forward Combat in DOOM). The result "emphasized brutality, aggression and speed" (Game Developer: Video: The combat design of DOOM). The Level Design Book sums up the series' combat: "Doom is clearly not about aiming" (The Level Design Book: Combat design).

DOOM Eternal (2020) responded to a criticism of the first game's structure, which Martin summarised as "hallways to the next arena, fight, hallways to the next arena, fight" (GameSpot: Why Doom Eternal Incorporates Puzzle…). GameSpot describes "more spacious combat arenas" with monkey bars, wall climbing and a double dash (GameSpot: Why Doom Eternal Incorporates Puzzle…). Martin also wanted the spaces between arenas to engage the player "just as much"; by release he judged that "The combat between arenas is awesome; it's as good as the arenas in my opinion, if not better" (GameSpot: Why Doom Eternal Incorporates Puzzle…; Shacknews: Hell Razer: The Making of Doom Eternal…).

#The environment artist's part

Combat spaces are shared work. On Star Wars Jedi: Survivor, Ben Armstrong, map owner for the Koboh Observatory, lists himself as "responsible for planning, ideation, block-out, modelling, level art/decalling", and credits a level designer and a separate combat and encounter designer (ArtStation: Star Wars Jedi: Survivor Observatory Arena). On The Last of Us Part II, Edgar A. Martinez credits himself with "design blockout interpretation", set dressing and collision for a combat space, alongside design, props, textures, lighting and FX (ArtStation: "The Last of Us: Part 2" - Med - Ratking…).

Three responsibilities follow for the art pass:

• Keep the metrics. Art that replaces a blockout cover block must keep its height band and footprint (The Level Design Book: Cover). See blockout.
• Match collision to the visual. "Fuzzy" cover, where it is unclear what blocks shots, frustrates players unless it is a deliberate choice, as in ARMA (The Level Design Book: Cover). See collision meshes.
• Make cover readable in a realistic setting. Furniture, rubble and architecture must still read as low or high cover from a distance (The Level Design Book: Cover). See set dressing and art passes and visual hierarchy and readability.

#How to set one up

These steps work in any level editor that can build a greybox; see level editors and blockout tools for the options.

1. Fix the metrics. Write down cover heights and player sizes before building; Uncharted 4's bands (under 0.5 m, 1.0–1.25 m, 1.75 m and over) are a good starting point (The Level Design Book: Cover). Build them into a gym level.
2. Block out the arena shape. Start with an open area or three lanes (The Level Design Book: Combat design).
3. Plan the entry. Add a vista where players can read the layout and a one-way drop or closing door (The Level Design Book: Encounter design).
4. Place cover sparingly. Begin with fewer pieces than you think you need, then add only where testers feel exposed (The Level Design Book: Cover).
5. Add loops and a flank. Remove dead ends, and give at least one route that reaches behind the main cover line (PlayStation Blog: Classic levels deconstructed: the beautiful…; The Level Design Book: Cover).
6. Add height. Give one area of high ground that is reachable but exposed (The Level Design Book: Cover).
7. Place enemy entrances. Choose where reinforcements arrive and what triggers them (The Level Design Book: Encounter design).
8. Playtest, then dress. Keep cover heights and collision the same during the art pass. See playtesting spaces and telemetry and heatmaps.

#Video tutorials

#Use in recent games

• Star Wars Jedi: Survivor (Respawn, 2023). The Observatory arena on Koboh was planned and built by one map owner from block-out to decals, with separate level and encounter designers (ArtStation: Star Wars Jedi: Survivor Observatory Arena).
• DOOM Eternal (id Software, 2020). Larger arenas with traversal tools, and combat spaces between arenas that the director rated as highly as the arenas (GameSpot: Why Doom Eternal Incorporates Puzzle…; Shacknews: Hell Razer: The Making of Doom Eternal…).
• The Last of Us Part II (Naughty Dog, 2020). A combat space modeled and dressed from a designer's blockout, with collision by the environment artist (ArtStation: "The Last of Us: Part 2" - Med - Ratking…).
• Uncharted 4 (Naughty Dog, 2016). Fixed cover-height bands used across the game (The Level Design Book: Cover).
• DOOM (id Software, 2016). Arenas built without cover as a mechanic, with loops and line-of-sight breaks (Game Developer: Video: The combat design of DOOM; PlayStation Blog: Classic levels deconstructed: the beautiful…).

#Further reading and watching

Related pages: sightlines and vistas, layout and flow, pacing and intensity, set pieces, blockout, prospect and refuge.