Poison, Burn, and Bleed are the status ailments that deals damage every turn, regardless if it's Lex or not. Some enemies use these against Lex. While Lex can put these status ailments to enemies if he has the Amethyst (for poison status) or Ruby (for burn status). Lex must need a treasure in order for him to put a Bleed status to an enemy.
In Bookworm Adventures Vol. 2, Reflected damaged and Cursed damage are new types of damaging status aliments, only when Lex used cursed tiles or when you attack with an active reflect shield. Also, a badge can be obtained if Lex defeats an enemy by just any of these status ailments.