Unexplained Red Precipitation

This page is the CodyCross answer for the clue below from Comics, Group 1073, Puzzle 3 (Editing Notes).

Question is: Unexplained Red Precipitation

and the answer is: BLOODRAIN

Word Meaning:

BLOOD RAIN — Rain coloured red due to the presence of spores of the microalga of species Trentepohlia annulata

Definitions from Wiktionary.