Beware Those "leaves of Three"
This page is the CodyCross answer for the clue below from Comics, Group 1064, Puzzle 1 (Heroes and Villains).
Question is: Beware Those "leaves of Three"
and the answer is: POISONIVY
Word Meaning:
POISON IVY — Any of three ivy-like species of Toxicodendron, known for their ability to cause an itching rash and blistering for most people, through urushiol, an oil that is a skin irritant.
Definitions from Wiktionary.