D&D Astral Sea Battle Mat: How to Set Up Spelljammer Encounters

By WizKids Store | Published: 2026-10-31

Category: How-to Guides

Learn how to set up the D&D Icons of the Realms Astral Sea Battle Mat for Spelljammer ship combat, from grid orientation to miniature scale and mat care.

Quick answer

Lay the Astral Sea Battle Mat flat with the printed side up, anchor it so it does not shift during ship combat, and use the 36-inch square area to position Spelljammer miniatures and track movement on a clear grid. Then add terrain markers and keep the neoprene back clean to protect the map.

Why the mat's size and material matter for ship combat

The Astral Sea Battle Mat measures 36 by 36 inches, giving you a large square play area for Spelljammer encounters. That space lets you place multiple ship miniatures and still leave room for crew figures and obstacles. The single-sided full-color map shows the Astral Sea on the printed side, while the back is tough neoprene. The neoprene gives the mat a slight grip and cushion, which helps it stay put on a table and makes picking up miniatures easier than on a hard surface.

Because the mat is single-sided, you cannot flip it for a different terrain. Plan your encounter around the Astral Sea artwork, or use removable markers to suggest other locations. The mat does not come with a printed grid overlay, so if you need a grid for D&D ship combat, use a clear grid template or measure distances directly. The absence of a built-in grid is a deliberate tradeoff: it keeps the artwork unobstructed but requires you to bring your own measuring tool.

Matching Spelljammer miniatures to the mat

The mat is designed to work with D&D Spelljammer: Adventures in Space and the related Spelljammer miniature sets. Most official Spelljammer miniatures are scaled for standard D&D combat, so they will fit comfortably on the 36-inch surface. For an astral dreadnought encounter map, place the dreadnought miniature near the center and arrange smaller ship miniatures around it at a distance that reflects the scale you use for ship movement. If you use a ship-combat grid, decide whether each square represents a fixed number of feet or a ship-relative distance, and keep that consistent for the whole encounter.

If your collection includes miniatures from other ranges, check their base size against the mat's space. The mat does not enforce a scale, so you can adapt, but be clear with players about what each inch represents. A common mistake is mixing scales mid-fight, which makes movement and range confusing.

Step-by-step Astral Sea Battle Mat setup

Clear and prepare the table: Choose a flat surface at least 36 by 36 inches. Wipe it clean and dry so grit does not get trapped under the mat. Unroll the mat with the printed Astral Sea side facing up. If it has been stored rolled, place books or clean weights on the corners for a few minutes to help it lie flat. Checkpoint: the mat should sit flat without curling edges before you place any miniatures.
Anchor the mat and define the play area: The neoprene back provides some grip, but for active ship combat, place small non-slip pads or removable tape at the corners. Decide which edge is the players' side and which is the enemy side, and mark the center point with a small token if your encounter uses a central objective. Checkpoint: gently push the mat sideways; it should not slide more than an inch.
Establish your grid or measurement system: Since the mat has no printed grid, lay a clear acrylic grid or use a measuring tape. For D&D ship combat grid use, agree that each 1-inch square equals 5 feet for character scale, or define a ship-scale unit such as 1 inch equals 100 feet for vessel movement. Write the rule on a note card and keep it visible. Checkpoint: all players can state the scale before the first turn.
Place ship and creature miniatures: Position the largest ship miniature first, then add smaller ships and crew. For an astral dreadnought encounter map, put the dreadnought at the center or along one edge and arrange player ships at least 6 inches away to allow maneuvering. Keep bases from overlapping and leave space for spell templates. Checkpoint: every miniature has at least 1 inch of clear space around its base for movement.
Add terrain and condition markers: Use removable tokens, dice, or small pieces of paper to mark asteroids, debris fields, or spell effects. Avoid permanent markers on the mat. If you need to mark the map temporarily, use dry-erase markers only on a clear overlay, never directly on the printed surface. Checkpoint: all markers are removable and none are placed directly on the artwork.
Clean and store the mat after play: Wipe the mat with a soft, slightly damp cloth and mild soap if needed, then dry it completely before rolling. Roll the mat with the printed side outward to protect the artwork, and store it in a cool, dry place away from direct sunlight. Do not fold or crease the neoprene. Checkpoint: the mat is fully dry and rolled loosely before storage.

Product facts

D&D Icons of the Realms: Astral Sea Battle Mat: The Astral Sea Battle Mat is a single-sided full-color map measuring 36 by 36 inches with a tough neoprene backside. The large square size gives ample room for ship miniatures and crew, while the neoprene back helps the mat grip the table and resist sliding during play.
D&D Icons of the Realms: Astral Sea Battle Mat