With this deck, the goal is to commit suicide, or come very close to doing so, anyway. With any luck, Selenia will watch over you and keep you safe, and at the same time lead you to victory somehow. If not, at least you left on your own terms.

Your ideal setup is to play Ad Nauseam, protected by Angel's Grace or Soul Echo (or, slightly less effectively, Phyrexian Unlife). This allows you to take all the cards you want with impunity. Notably, even with Angel's Grace this will succeed in putting your life below 0, which can be important. After losing about 100 life and putting 80 or so cards in hand, you have access to a bunch of mana artifacts, as well as 0-mana creatures for fueling things like Culling the Weak and Cabal Therapy to make sure you don't just run into a counter. Angel's Grace will only protect you from negative life until the cleanup step, but that's plenty of time to get just 2 mana, play Sickening Dreams, and discard enough cards to take out all the opponents at once. (If you're depending on Phyrexian Unlife to live, this plan won't work because you'll get poison counters, and the game will be a draw.)

Failing that, you can Dread Return for Skirge Familiar (obviously after you discarded both of those cards to pay for Sickening Dreams), discard even more cards for mana, and run out Repay in Kind and/or Reverse the Sands. Skirge Familiar only makes black mana, and Blood Celebrant can't convert mana if you're already below 1 life, so Reverse the Sands requires care with your mana artifacts or any untapped lands you may still have.

If things get desperate, you may have to fire off an unprotected Ad Nauseam, but 1) you're playing the Suicide Machine so that shouldn't come as a surprise, and 2) even that can sometimes give you the tools you need to pull out a win, especially if you already have Skirge Familiar to fuel cards into mana.

Near-Death Experience is another win plan, and this deck is clearly suited for taking advantage of it. Hex Parasite serves as a free life sink once you drop it, as does Selenia herself (you can certainly pay 36 life for 18 bounces in a row just to get rid of the life; only the first bounce will do anything, but you don't care, and in fact Selenia is often useful to have in hand just so you can discard her to a cost). Both of those only throw away even increments of life, so if you get stuck on even parity, there are plenty of ways to nug yourself for an odd number: Tarnished Citadel, Cabal Pit, Caves of Koilos, fetchlands...Vendetta and Reanimate can double as both board control and a way to lose a controlled amount of life; Snuff Out and Dismember don't quite give as much control over the amount of life loss, but they can help make sure you only drop to 1, not below that, and on your terms, not your opponent's. NDE uses an intervening-if clause, meaning you have to be at 1 before anyone even gets priority in the upkeep if it's going to work at all, so you have to act in the previous turn's end step with your life dump. If it works, great. If the opponent is slow-rolling Gut Shot, well...not much you could have done about that anyway. Except build up to Plan A.

If you're ever the victim of a bad beat that makes you want to kill yourself, do yourself a favor. Limit it to the simulated death that is Suicide Machine.


Updates Add