Type: Inhaled Poison

Description: The Necrotic Miasma is a concoction of decay and dark magic, filling the air with a thick, unbreathable gas. Crafted by a nefarious alchemist or mage, this poison combines volatile necrotic energy with the natural gases of decomposition to create an environment that is not only toxic but suffocating. The air is so saturated with poison that even successfully holding one's breath does not prevent the inhalation of trace amounts of the toxic fumes.

Trigger: The Necrotic Miasma is typically encountered in enclosed spaces such as dungeons or tombs, released when adventurers disturb the air or trigger a magical or mechanical device designed to release the poison.

Initial Effect: Upon exposure, all creatures within the area must make a DC 15 Constitution saving throw at the beginning of each turn spent in the miasma:

• On a Failed Save: The creature takes 1d6 acid damage (representing chemical burns) and 1d6 poison damage (representing respiratory distress), and suffers from the Poisoned condition.
• On a Successful Save: The creature does not take damage or become poisoned, but the toxic nature of the air means they do not receive any actual oxygen; continued exposure can lead to suffocation.

Secondary Effects: Continuous exposure to the Necrotic Miasma can lead to long-term health issues:

• Extended Exposure: Every consecutive round a creature remains in the miasma, the DC for the Constitution saving throw increases by 1. If a creature fails three saves in a row, the damage from both acid and poison increases to 2d6 for each type.
• Suffocation: Creatures relying on breathing can begin to suffocate, as the miasma makes the air unbreathable. Rules for suffocation in D&D state that a creature can hold its breath for a number of minutes equal to 1 + its Constitution modifier (minimum 30 seconds). Once this time is up, they can survive for a number of rounds equal to their Constitution modifier before they drop to 0 hit points and are dying.

Cure/Antidote: The effects of the Necrotic Miasma can be mitigated by:

• Magical Healing: Spells such as Lesser Restoration to end the Poisoned condition, or Protection from Poison to grant resistance to the poison damage and advantage on saving throws against being poisoned.
• Antidote: An antidote can be formulated from rare herbs found in non-toxic environments, typically requiring an alchemy check or the use of a spell like Detect Poison and Disease to identify and harvest correctly.