Back to the canon characters. Discord was a pretty clear choice for the Devil, which represents temptation, corruption, and the shadow self. I mean, in his intro story, he was literally flip-flopping characters' personalities. Inverted, this card means exploring dark thoughts and releasing limiting beliefs. Like Death, the Devil is not an inherently evil card -- exploring dark thoughts and letting loose every now and then are not evil in and of themselves, and can allow people to better understand themselves and the world around them.

Symbolism! The eight arrows are a symbol of chaos, while the grapes are symbolic of luxury and addiction. The collar at the foot of the throne is symbolic of captivity, but it sits loose and open -- one must choose to put it on themselves.