Currently Darkness and Aether would stand to gain a lot through Nightmare, Fractal and Mindgate. Darkness causing negative effects for the opponent and Aether causing positive effects for yourself. Fractal and Mindgate both fill up the hand very well, and using the card advantage Aether is so good at for something more would be very, very interesting.
Death is linked to sacrifice of course.. it would make sense that the element could stand to gain from discarding certain cards. A negative effect for your opponent seems the most logical.
...unintentionally I just displayed three ways for this mechanic to work. Your opponent discarding something and losing from it, you discarding something to gain from it, and you discarding something to hurt your opponent.