If you do, draw X cards, where X is the number of cards you discarded
Completely useless, unless youre already way ahead of your opponent
Luckily, there are means of circumventing this drawback, such as the card Conjurer's Closet, which allows you to blink any of your creatures, washing them of their Nightmare typing before they'd be exiled from Chainer's death
Granted, it would take 6 mana to lay this guy out and cast a Moonmist for an effective all-out assault in one turn, but in a green and red deck, that could easily happen by turn 4 or 5
Additional Combat Phases would also be of great use here as opposed to trigger doublers like Strionic Resonator or something
The subscription runs about $9/mo, which makes it the most expensive option on this list by a wide margin