But how do you use your rebound spells to best effect, and how can you evaluate these spells that come back for more?
Some creatures are better at rebounding than others. While many of the creatures in Rise of the Eldrazi like Wall of Omens and Lagac Lizard don't get much better when surrounded by rebound spells, there are also a couple of rebounding all-stars floating around.
The two best rebounders in the set are without a doubt Mnemonic Wall and Kiln Fiend.
While Mnemonic Wall and Kiln Fiend are fine when complemented by good, normal, non-rebounding spells, these are cards that only reach their full potential when aided by Staggershock and friends.
Mnemonic Wall tends to be at its best when it's bringing back rebound spells. When you are getting four uses out of a Staggershock, it won't matter if you are picking off your opponents creatures, hammering away at your opponent's life total while you are busy swinging in with evasion creatures, or some combination of the two, your opponent is sure to be in for a world of hurt.
While you are getting extra uses out of your rebound spell thanks to your Mnemonic Wall, you are also getting a creature with a large enough backside to stop Kozilek's Predators, Emrakul's Hatchers and Lagac Lizards dead in their tracks.
While you currently don't want to take Mnemonic Wall too early before you've seen how your deck is shaping up, if you are trying to put together a slow, grinding blue-red good stuff deck, there are few cards that are better to have than this 0/4.
Please note, however, that in a few weeks/months, when the format matures more, Mnemonic Wall could easily be considered a first pick card. But right now, you probably are best off waiting until you get a few picks deep in your packs before taking this regrowing wall, unless you already have a bunch of awesome spells like Staggershock to bring back.
I'm a huge fan of Kiln Fiend. Yes, it's somewhat fragile. However, at a mere two mana, it has the ability to run away with games in a way that few other cards in the set do.
If your opponent gets off to a slow start and doesn't have a way to deal with your early Kiln Fiend, then he or she probably won't get the chance to even cast any of his or her relevant cards.
Heck, even if your opponent does have a decent start, if you have some Staggershocks and/or Distortion Strikes and your opponent doesn't have a removal spell, it won't matter what creatures he or she plays. A Kiln Fiend plus two Distortion Strikes is, after all, a turn four kill.
Like Mnemonic Wall, Kiln Fiend's value depends on how many spells, particularly how many rebound spells you've picked up during the draft. Early on in the draft, you might not want to take Kiln Fiend too high. But if you have a lot of good instants and sorceries (especially rebounders), or your draft has gone awry and you need a way to steal some wins, then you might find yourself taking Kiln Fiends with some of your earliest picks in the second and third packs.
Distortion Strike wound up being a lot better than I originally thought it would. My first inclination was to compare it to cards like Wave of Indifference that could act as solid finishers for aggressive decks that needed a way to break through, but would often have very limited utility. When I was comparing Distortion Strike to Wave of Indifference, Distortion Strike came out looking pretty bad. It was a far less reliable finisher, as it only makes one creature unblockable on each of two turns, and it only takes a single removal spell or bounce spell to throw the whole thing off.
But rather than think of it as the finisher that I use to end the game, I learned that Distortion Strike would often be used to punch through 8-10 damage on a slightly clogged board, without forcing you to alpha strike (leaving you defenseless against counterattacks) to get in that big chunk of damage.
Then, there are some creatures that combo particularly well with Distortion Strike. For example, Valakut Fireboar gets in for a whopping 7 damage with the aid of a Distortion Strike, and Kiln Fiend, of course, becomes quite monstrous when enhanced by a Distortion Strike.
Emerge Unscathed, while definitely good, turned out to be a bit weaker than I had originally thought it would be. Yes I still want it, and will main-deck it in almost any white deck, but there are plenty of other, far more essential cards, that I would want to take over it. I feel comfortable thinking of Emerge Unscathed as a 20th-21st card for my deck, one that I would be happy to pick up late in a pack, but unhappy to have to take early.
While it isn't one of the best cards in Rise of the Eldrazi, Prey's Vengeance is without a doubt, one of my favorite cards in the set. No, it isn't nearly as powerful as it would have been in Zendikar / Worldwake Limited, but it's still quite good. If I'm drafting an aggressive green deck, then it's incredibly valuable to have the ability to win an otherwise losing combat. That then allows my Nest Invader or Kozilek's Predator to crash in unscathed for 4-5 damage at the low cost of a single green mana.
Heck, if I'm drafting a slower green deck, it can be just as, or even more important than the above scenario, to have a way to keep my Overgrown Battlement alive in the face of a Flame Slash, or a well timed Staggershock.
I will generally look to take Prey's Vengeance about 3rd-5th in aggressive decks, and about 4th-7th in slower green decks.
Surreal Memoir tends to be a bit too slow and a bit too unreliable for play in normal matchups, but in slower matchups, Surreal Memoir can absolutely shine. If you bring it back with Mnemonic Wall, you can get a flow of spells that can seemingly last forever. But even when it would be at its best, you shouldn't look to pick up Surreal Memoir until you get deep into the pack.
Survival Cache is a card that I would definitely prefer not to play, and wouldn't waste a pick on, but I would not feel terribly bad about including in my deck. The problem with Survival Cache is that it never does that much for you, and will often do next to nothing. If you are ahead on the board and ahead on life, then the life gain probably won't mean that much to you, and you will be getting a slightly delayed Divination.
While that effect is fine, you would often be better off trying to spend that time furthering your board so that you can continue to press your advantage.
If you are behind on life, then you will either have to sit on Survival Cache until you get ahead, or blow it for a mere 4 life. Either way, you won't be getting much value out of your sorcery.
Virulent Swipe is interesting in that it is often used for fairly defensive purposes when you cast it initially, allowing your pint-sized blocker to take down something quite large and intimidating; and then for purely offensive purposes on the rebound, making one of your other undersized critters ready to punch in for a decent chunk of damage in the face of your opponent's much more menacing creatures.
In hyper-aggressive decks, and in decks with a lot of Eldrazi Spawn token generators, I'd be content to start a Virulent Swipe or two, but even then I wouldn't want to take it during the first half of a pack. Otherwise, I'd leave the one mana instant rebounder on the bench. While I wouldn't want to start Virulent Swipe in most decks, I'd be more than willing to crash the boards for it if my opponent had some large, must kill creatures, in his or her deck.
The very existence of Virulent Swipe leads to a lot of interesting combat situations late in the game.
If you have an instant speed removal, bounce, or counterspell, then you probably won't want to block out of fear of Virulent Swipe, knowing that you could simply take the 2 damage, untap and have a ready answer(s) to the instant that gives a creature deathtouch for the turn.
If you don't block, you have to realize that that communicates that you probably have an answer in your hand, a fact that your opponent will definitely take into account on subsequent turns.
But if you are fairly low on life, this might be exactly what your opponent wants you to do, and by not blocking, you are giving your opponent the very opportunity that he or she needs to outrace your monstrous Eldrazi creature.
If you don't have an instant speed answer, then you will have to decide if you think it's worth giving up the chance to draw an answer and the annihilator 2 that you would get out of your Artisan of Kozilek in exchange for the ability to save 2 damage and have the very real chance of calling your opponent's bluff—catching him or her without that Virulent Swipe.
Even if you have an instant speed answer, you will have to decide if you think the 3 damage that the Bloodrite Invoker would do to you, plus the subsequent drain life effects from its activated ability are worth risking losing your oversized Eldrazi to your opponent's Bloodrite Invoker. Even if you don't block in that spot, your opponent might use his or her Virulent Swipe to pump his or her Bloodrite Invoker to get in for 5 damage before draining you for 3 more.
Pretty much anytime that you or your opponent has a black mana open, and attacks a creature into a much larger blocker, then you, and consequently your opponent, have to be thinking of Virulent Swipe. Just be careful not to psyche yourself out too much thinking about the deathtouch granting instant, because attempting to play around it will often be far more devastating for you than whatever effect your opponent would have gotten by using his or her spell and his or her creature to trade with your larger threat.