Propose Dungeon Trait: Environment: Environment 0 [Environment*0], dungeon is made purely of local materials, and is like a simple cave, no stone walls of any sort.
Environment 1 [Environment*1], dungeon has reinforced walls, weak materials like logs are used, but the walls are still of local materials.
Environment 2 [Environment*2], dungeon has covered walls, the walls are flimsily covered with materials like logs and planks, but a solid cave in is still a threat.
Environment 3 [Environment*4], dungeon has simple structure walls, most likely stone brick, so it's protected against cave ins, and has gone from a large cave to a proper dungeon. Dungeon can also have slight elemental properties, or environment unnatural to the area. Warm caves, cold caves, caves with crystal walls. Even vents of steam, or frozen parts.
Environment 4 [Environment*8], dungeon has structure walls, like smooth bricks, or crystal walls. Cave ins are almost impossible, and even has steel parts. They can also be very hot caves, capable of containing boiling pools of water, pools of acid, the entire cave can be frozen.
Environment 5 [Environment*16], dungeon is either masterwork structure, granite bricks, engraved bricks, even enchanted brick, capable of moving without machinery, to change the dungeon. Magma caves can be present, pools of animate slime, frozen mist can drift around.
Environment 6 [Environment*32], dungeon is definitely enchanted, golems and animate guardians dot areas of importance, if broken, they will slowly repair, and come online after a month or two. Magma caves contain animate magma beasts, or even fire elementals, acidic environments are toxic to breathe in, requiring masks for survival, while frozen areas have animate ice golems, rocky caverns can reshape at will, with the earth itself sometimes coming to life. Air caves have vents of air push people around, with the air itself collecting with a will of it's own.
Environment 7 [Environment*64], dungeons can alter itself a lot, arcane cogs are operate without external power until the end of time. Fire caves are too hot to even breathe in, without some sort of ward. Ice caves slowly freeze any who enter without a ward. The air caves have winds strong enough to tear people to shreds. Rock caves can even end up having less air, making combat difficult without some sort of ward against this effect.
Environment 8 [Environment*128], dungeons are phased into the arcane plane, the shifting doesn't have to follow physical laws, and can even phase into itself. Fire caves contain massive amounts of magma, with sulfurous fumes killing all who breathe it. Ice caves freeze water in an instant, and contain rivers of liquid nitrogen and other gasses. Earthen caves shift like a living creature, and might even be alive. Living caves of flesh can exist. Air caves has pressure so powerful it crushes humans without powerful wards.
Environment 9 [Environment*256], dungeons contain eldritch guardians who are part of the dungeon's consciousness. Fire caves contain magma demons. Ice caves have ice demons. Earthen caves have demons of earth. Air caves have demons of storm. The dungeons will cause natural disasters in the surrounding areas if not regularly purged.
Environment 10 [Environment*512], dungeons are made of blackrock, which cannot be damaged by any physical force. It also shifts with absolutely no regard for physics. If it shifts walls into each other with someone between them, they are simply disintegrated. The golems of this place are indestructible, and can phase into non-corporeality, to bypass physical barriers. Fire caves burn everything that enters, only the strongest wards can ward this off. Ice caves reach absolute zero. Earth caves move with great agility. Air caves have no solid ground, it's instead just dense air, like clouds you can walk on. The elemental caves serve as sources of elemental power.