Dungeon Brick Walls

The Dungeon Brick Walls are the colored background Walls that can be found in Dungeons. These can be harvested either with a Hammer, or by using Dynamite. Dungeon Bricks cannot be crafted. Dungeon Brick Walls share the same properties as Dirt Walls, including that map-generated dungeon walls will not prevent the spawn of enemies, while those placed by the player do prevent spawning.

The type of dungeon wall present in an area of the Dungeon affect what type of Hardmode Dungeon enemies will spawn after defeating Plantera. The Faction Flags present in each area of the Dungeon are an indicator of what will spawn there, but are not the cause of the spawns themselves.

Pre-1.2/Non-PC Versions
necromancers suck