According to the Washington Post, the threat that was reportedly made by El Chapo to ISIS was apparently a hoax.
The original story was that El Chapo was very upset after finding out that the Islamic State was destroying his drug shipments in the Middle East. The information regarding the threat was supposedly found by a Mexican blogger, who leaked the email.
Guess where the email was actually first appeared? On the website Thug Life Videos. Got dammit! If you don't know about Thug Life Videos, it's a website that publishes music videos, news, and satire. Thug Life Videos writer Steve Charnock said to Snopes.com "Maybe I didn't make this El Chapo story funny or weird enough, though. Or I just have an uncanny ability to ape how Mexican drug cartel kingpins talk."
Alright guys. Looks like there won't be a brawl between El Chapo and ISIS...