Name a gas found in Earth's atmosphere

A prompt from the Krillion daily dive of September 17, 2026 (Dive #64), prompt 7 of 7.

Answers worth giving

201 accepted answers on the game's sheet for this prompt.

Shown here: a selection of 8, best-scoring first. Recorded from a third-party archive of the official sheet.

Answers for: Name a gas found in Earth's atmosphere
Answer	Tier	Points
IsopreneTrees release it, and it makes the Blue Ridge haze.	One in a Krillion	100
Sodium vaporAstronomers fire lasers at this layer to make artificial guide stars.	One in a Krillion	100
(Z)-3-hexen-1-ol	Deep Cut	85
Argon	Schooler	30
Carbon monoxide	Schooler	30
CFCs	Schooler	30
Helium	Schooler	30
Hydrogen	Schooler	30