# Deep Dragon ## Lair Actions _Source: Fizban's Treasury of Dragons_ On initiative count 20 (losing initiative ties), the dragon can take one of the following lair actions; the dragon can't take the same lair action two rounds in a row: - **Deep Torpor.** The dragon casts the [slow](/Rules/Source/spells/slow-xphb.md) spell, requiring no spell components and using Charisma as the spellcasting ability (spell save DC 16). The spell ends early if the dragon uses this lair action again or if the dragon dies. - **Mossy Sludge.** The dragon conjures sludge-like moss that briefly covers surfaces in the lair. The ceiling, floor, and walls of the lair become difficult terrain until initiative count 20 on the next round. - **Toxic Spores.** The dragon fills a 20-foot cube it can see within 120 feet of itself with toxic spores. Each creature in that area must succeed on a DC 15 Constitution saving throw or take `dice:4d6|noform|noparens|avg|text(14)` (`4d6`) poison damage and be [poisoned](/Rules/Source/conditions.md#Poisoned) until the end of its next turn. ## Regional Effects _Source: Fizban's Treasury of Dragons_ The region surrounding a legendary deep dragon's lair is altered by the dragon's magic, creating one or more of the following effects: - **Preservation of Knowledge.** Books, letters, and any other physical forms of writing within 6 miles of the dragon's lair become magically charged and can't be damaged by nonmagical means. - **Restless Sleep.** When a creature finishes a long rest within 6 miles of the lair, the creature must first succeed on a DC 10 Constitution saving throw or be unable to reduce its level of [exhaustion](/Rules/Source/conditions.md#Exhaustion). Creatures immune to the [poisoned](/Rules/Source/conditions.md#Poisoned) condition are immune to this effect. - **Verdant Growth.** Vegetation and fungi within 6 miles of the dragon's lair grow faster and cover a greater area than they normally would. Foraging in this area yields twice the usual amount of food. If the dragon dies, these effects fade over the course of `dice:1d10|noform|noparens|avg` (`1d10`) days.