NOTE: While this review specifically covers Standard PDC, you can still glean a bit of knowledge from the review as a Future Extended, Classic, or Block player.
What is PDC?
PDC stands for Pauper Deck Challenge. PDC is a Magic format that limits decks to commons only. This means uncommons and rares are not allowed in the format. Timespiraled cards are also illegal.
What are popular decks in PDC?
Like any Magic format, there are Decks to Beat (DTB). PDC is no different. Fortunately, the metagame is quite varied with a mix of Aggro, Control, and Combo available. Here is a list of some of the popular decks running around in the PDC metagame as compiled by Kehmesis in this thread.
Storm Control (Control/Combo) - Uses a suite of red removal and counterspells to stall the opponent's board while it sets up a large Empty the Warrens storm using suspend cards.
Grimdrifter (Aggro/Control) - A midrange deck, Grimdrifter uses a plethora of creature removal spells to maintain board control while your creatures turn sideways. The deck can also run into the lategame as it has a large amount of card advantage.
Dark Evocation (Control) - Uses removal and its creatures as chump blockers to hold out until midgame and lategame when the deck can get it's Blightspeaker or Grim Harvest engine going to win through attrition.
Use UR Illusions (Aggro) - Similar to a Red Deck Wins style of play, this deck instead uses Blue creatures with evasion as beatsticks while still throwing burn to the face and to blaze a path for it's creatures.
Blue Beats (Aggro/Control) - Uses evasive blue creatures to beat while taking board control with a variety of counters.
Red Deck Wins (Aggro) - A simple play style involving attacking with creatures and using burns to remove blockers and as a finisher.
White Weenie (Aggro) - Play low CMC creatures and attack into your opponent.
Rating System
My ratings are based on the sets in the current format, including this set. I will not rate a card higher because of it's future potential (ie: a runner up replacement to a popular card currently in the format). It is possible a better card than the runner up may come in future sets or the metagame may change entirely where that card is no longer good. Because you cannot predict the future, all cards are rated according how good they are NOW.
1/5 = This is a bad card and will never see play in an experienced player's deck.
2/5 = This is a fringe card and might have potential in one or two very specific decks.
3/5 = This may be a good or bad card, but requires a deck built around it to become powerful.
4/5 = This is a solid card and will see play in decks of it's main colors.
5/5 = This is a powerful card due to it's inherent less conditional usage.
Artifacts
Blazethorn Scarecrow
1/5
The body is overcosted for it's P/T. The additional abilities are not worth the extra two mana. There are three drops, like Bloodrock Cyclops and Nessian Courser, that are more better than this.
Blight Sickle
2/5
Is the Wither ability worth 4 mana? I asked Cinderbones if it was worth 1 mana. The answer is most likely no.
Chainbreaker
1/5
Hes 2 mana for a 3/3 body. That's damn good. Oh wait. 8 mana for a 3/3 body. The only thing he does well is combo with Fate Transfer. Even that combo is not very good, as it suffers from the same inherent card disadvantage problems as enchantments. It is unlikely that you will see card advantage from Chainbreaker + Fate Transfer.
Elsewhere Flask
2/5
Since Jaws of Stone and the rest of the series are uncommon, I don't see how this would be relevant except for color fixing.
Pili-Pala
1/5
The {Q} ability is nice, but Horshoe Crab is the better alternative to machine gun Power of Fire or Presence of Gond. Horshoe Crab has a bigger butt, so he can survive Shock, Tarfire, or Hurly-Burly.
Rattleblaze Scarecrow
2/5
If playing red, I see no reason to run this over Scuzzback Marauders. If playing Black, there are more powerful cards to splash for, such as Auroch's Herd.
Scrapbasket
1/5
The ability is nice with the new auras and cohort bonuses, but the body is too small for it's cost.
Scuttlemutt
2/5
It's mana acceleration comes too late and it's other ability can only shut down the new auras or cohort bonuses.
Thornwatch Scarecrow
2/5
For green, Auroch's Herd is a better creature. For White, the mana cost is too high as you are most likely playing White Weenie.
Watchwing Scarecrow
3/5
This is the best scarecrow of the bunch. His butt is naturally out of Incinerate range and serves as a good blocker. With the color bonuses, this scarecrow becomes both an evasive attacker and a hard to kill blocker.
Wingrattle Scarecrow
2/5
For black, while Persist is nice, it leaves you with a 1/1 body. Without the blue bonus, he is simply a Scathe Zombies. Even with the bonuses, he is lackluster.
Hybrid
(Æthertow)
2/5
Four mana for removal is simply too expensive. There are better alternatives like Last Breath and Oblivion Ring.
Barkshell Blessing
1/5
There is little reason to run this over Giant Growth or Earthbrawn. Earthbrawn has the potential to give a permanent +1/+1 counter and Giant Growth will put an X/1 creature out of burn range without having to conspire anything.
Barrenton Cragtreads
1/5
Steelhead of the Godhead attaches well to this body. However, there are better alternatives, like Ballynock Cohort.
Cultbrand Cinder
1/5
This creature is overcosted. By the time you reach 5 mana, the opponent will likely have a creature larger than this or possibly a creature with evasion.
Curse of Chains
4/5
This card reads "Pacifism for Blue." Holy Crap. Blue rarely gets removal like this. The next best cards are Piracy Charm and Erratic Mutation, both of which are subpar.
Elvish Hexhunter
3/5
A good sideboard card in a possible meta of auras. It is also good as a mainboard card if you are running auras yourself, specifically Shield of the Oversoul.
Emberstrike Duo
1/5
There are not enough Hybrid cards to make this creature good when there are already plenty of other higher powered two drops.
Fate Transfer
2/5
This is a card I think someone will try to break. But looking at this set though, I don't know if it is possible. There are few cards that this card can combo with. It also suffers the same card disadvantage fate as auras.
Fists of the Demigod
1/5
This card suffers from the same card disadvantage problem as other auras. On top of that, while it is a lot cheaper to play, it is a lot less powerful than the other auras in the cycle.
Giantbaiting
3/5
This card turns your early turn drops into big creatures for a turn. It be key to future versions of decks like Mono Green Aggro, Elves, or Red Deck Wins.
Gravelgill Axeshark
1/5
This creature is impressive, but for 5 mana you can simply get a creature with a larger body or a creature with evasion to push through that last damage.
Gravelgill Duo
1/5
Three to cast for a 2/1 body is already terrible. Additionally, there aren't enough hybrid cards to make this great.
Helm of the Ghastlord
2/5
Suffers an inherent card disadvantage problem. On top of that, if you connect with it once, you've probably already won the game as your opponent as no creature removal in hand. This card seems like a win more card.
Loamdragger Giant
1/5
While games do make it to 7 mana without mana acceleration, I wouldn't count on it. With mana acceleration, you can probably run better early drops, such as the new Hungry Spriggan.
Manaforge Cinder
1/5
The body and ability are not good. If you do need the mana fixing, you should improve your mana base or consider other options like Prismatic Lens or Elsewhere Flask.
Manamorphose
4/5
This card is incredible to increase your storm count or even just cantrip for free. An auto-include into decks like Red Deck Wins and Storm Control that use the Storm mechanic.
Medicine Runner
3/5
The body is decent, but most importantly, it allows you to reuse your persist creatures by removing a -1/-1 counter. Additionally, it attaches well to Shield of the Oversoul, the best aura in the cycle.
Memory Sluice
1/5
Decking is a no-no.
Morselhoarder
2/5
While he is really a 6/4 for "only four mana," if you have no mana acceleration or outlets for removing the -1/-1 counters, he is still six to cast for a 4/2 body.
Mudbrawler Raiders
1/5
This is plainly a 3/3 creature for four mana. Blue mages are likely to counter this creature. They would rarely even try to chump block this guy, even without his conditional evasion, as it would be better to simply race you.
Old Ghastbark
1/5
For 5 mana, I would rather have a Crabapple Cohort.
Oona's Gatewarden
1/5
A one drop for Faeries that allows a turn 2 Spellstutter Sprite for 2. Problem is that Faeries wants to be on the offensive.
Poison the Well
2/5
This card is better than Demonlish, but at four mana the land destruction will come too late, after the opponent has reached the key two or three mana. On the plus side, it does two damage.
Raven's Run Dragoon
1/5
For four mana, this card is subpar for both White and Green. Both colors have more powerful creatures for less mana, like Ballynock Cohort or Hungry Spriggan. On the plus, he goes well with Shield of the Oversoul.
Runes of the Deus
2/5
While this aura costs an incredible 5 mana, this card is so powerful that if you are able to connect once with both of the bonuses, you will probably win the game. At 5 mana and with few playable creatures that get both bonuses, this aura is not likely to be a strong contender.
Safehold Duo
2/5
Serves as a good blocker and survives an Incinerate. Probably the best candidate for Shield of the Oversoul.
Safehold Elite
3/5
A Grizzly Bears with persist is not bad. Medicine Runner will remove that -1/-1 counter from persist.
Safewright Quest
1/5
This is not mana acceleration, but rather mana fixing. Green has better alternatives like Llanowar Elves and white already has generally low CMC.
Scar
2/5
Better than Shock or Skred? Rarely. On the plus, it shuts off persist.
Scarscale Ritual
3/5
Draw two is always good. The problem is that it almost reads, "sacrifice a creature, draw two cards" since putting a -1/-1 creature on a 2/2 will leave you will a poor body.
Scuzzback Marauders
4/5
This guy is great. He is best comparable to a Ball Lightning with Persist. Even if he gets chump blocked, he still pushes through damage because of his trample and will come back again to finish the job. At worst, this creature will eat two of your opponent's removal spells, leaving you with less to worry about.
Scuzzback Scrapper
2/5
This guy is no Sickle Reaper. Green has better one drops already. Karpulsan Wolverine is a better alternative.
Shield of the Oversoul
3/5
This is probably the strongest in the aura cycle. If you enchant the creature, they become indestructable. The White part that grants evasion is simply a bonus. This is still good in a mono-green deck.
Silkbind Faerie
2/5
This guy can tie up the combat phase, but he and his ability are expensive compared to Goldmeadow Harrier. However, he is a prime creature to attach with Steel of the Godhead.
Somnomancer
3/5
In any tempo-oriented deck, such as White Weenie, forcing an extra combat phase through may win you the game. His tempo is best comparable to Pestermite, who can tap out your opponent's most recent three or four drop. Additionaly, she is a Kithkin, so she can trigger off the condition clause in Surge of Thoughtweft in White Weenie decks.
Sootstoke Kindler
1/5
The body is too small for it's casting cost. Even his ability comes into the two colors that do not have very powerful mid or late game drops.
Sootwalkers
2/5
At best, he will see play as a sideboard card in RDW against WW, which sometimes has problems forcing damage through after WW has stabilized with life gain. At worse, he will remain unplayed like the rest of the cards of the Hill Giants of this set.
Steel of the Godhead
3/5
Similar to Runes of the Deus, if this aura connects with both conditions, it probably puts you so far ahead of the race that the opponent is unlikely to recover. However, the enchanted creature is still vulnerable to removal.
Tattermunge Duo
3/5
With all the red instants available, this guy can get pretty big. Simply playing Brute Force will turn this guy into a monstrous 6/7 creature.
Thistledown Duo
1/5
The body is too small for it's casting cost. Additionally, the pump clause is white. White has very few playable instants to surprise pump with, meaning it will be hard to trick your opponent into not blocking this guy for fear of a white spell.
Torpor Dust
1/5
Curse of Chains is better for blue. Black already has removal spells.
Traitor's Roar
1/5
As a sorcery, this card is not good. If they have a huge monster, it is going to be tapped because they're simply going to attack to you with it.
Turn to Mist
3/5
This card can target enemy creatures, removing a blocker for a turn. It can even count as aura removal. Unlike Momentary Blink, it does not return the creature immediately, which means several combat tricks, like blinking a tapped creature to block, are out of the question. It also lacks the inherent card advantage of Momentary Blink. This card won't see as much play until Momentary Blink rotates out.
Wanderbrine Rootcutters
1/5
If the meta does become distorted due to Shield of the Oversoul being too good, this guy will count as an evasive creature that can run by that indestructible green man.
Zealous Guardian
1/5
1/1 creatures without relevant abilities are bad.
How Might These Cards Affect Standard PDC?
Unfortunately, after reviewing both the hybrid and artifacts of this set, there are not many powerful cards in this set. Too many cards require specific conditions to be powerful. Without support from other cards, they are not cost efficient. With the support of the cards, then they become a little better than cost efficient.
Several of the cards here will probably make it into the metagame. With Curse of Chains, some sort of MUC deck may be possible. I'm also pretty sure someone will try to build decks that incorporate Shield of the Oversoul as well as Steel of the Godhead. As to which aura is better, I would put my money in Shield of the Oversoul. Manamorphose is probably an auto-include in Storm Control, an already powerful deck. Whether that makes this deck even harder to beat is difficult to say. Scuzzback Marauders may seen overrated, but remember that it is in the same colors as Medicine Runner. Not to mention it works great with all-star Momentary Blink, giving it 4 lives to live!
Whether there will entirely new decks based entirely on the Shadowmoor cards, it seems unlikely since the Timespiral cycle is just far more powerful. Until that set rotates out with Coldsnap, I don't think there will be a huge change to the Standard metagame unless Eventide drags in something far better.