How about Smoke?

[Stonemason]

Since there is no Wind in BA there is no drifting smoke so the hindrance is restricted to the placement location otherwise you would need to include Wind and Wind Direction not to mention how strong the wind is.

Rain/Falling Snow: the only smoke that may exist is from blazes (terrain) or smoke grenades placed inside buildings. But since blazes block LOS, there is no real need to put smoke in that location anyway unless you had some kind of height advantage over the burning location which in BA we don't; as far as I know.

Night: smoke may be placed at night

Units inside the smoke have their fire power reduced because it's a lot harder to keep your eyes open when you are standing in smoke (anyone who has stood by a campfire and has had smoke going into their face can attest to that)

Also, smoke placed by smoke grenades should dissipate after the player's units have finished moving