Battle for Wesnoth

Deep beneath Jotha Castle, the Abyssal Vault is a hidden chamber carved from the bay floor's bedrock, concealed by layers of magically solidified coral. Access requires a specific sequence of water magic and manipulation of floor carvings to reveal a pressure-sealed entrance. Inside, treasures are displayed within geodes lined with anemones and secured in intricately carved shell coffers, illuminated by bioluminescent crystals. The air is clear and breathable, maintained by water filtration spells, while guardians in the form of animated coral sentinels protect this repository of Jotha's most precious artifacts.

The chamber is adorned with luminescent pearls on polished obsidian pedestals, and ancient artifacts suspended in shimmering water fields. The soft light from bioluminescent crystals creates a serene atmosphere, free from harsh shadows.