race features:
Darkvision: You can see in dim light within 60 feet of you as if it were bright light, and in darkness as if it were dim light. Your ancestors tie to the now defunct Para-Elemental Plane of Smoke made your ancestors' darkvision unusual: everything they saw in darkness was in shades of dark grey. This has been passed on to you.
Filtering Lungs: You have advantage on saving throws against harmful gases such as those created by a cloudkill spell, stinking cloud spell, inhaled poisons, and gaseous breath weapons.
Steer the Smoke: You know the Poison Spray cantrip. At 5th level, you can cast the Stinking loud spell once with this trait as a 3rd-level spell, requiring no material components, and you regain the ability to cast it this way when you finish a long rest. Constitution is your spellcasting ability for these spells.