Ahhh.... Green. I love this color. So far White and Red seem to have the best Gearhulks, and each color has gems I am interested in playing. I love artifact-matters blocks, and that's my bias.
Appetite for the Unnatural: Nice title! I would have preferred one less mana and old school Naturalize. The life gain does not have much of a theme in this standard.
Architect of the Untamed: Nice title! The Energy booster of the set, and it comes in early enough to make a difference. If the Energy economy is aggressively costed, this card will be a chase rare. If it is not, then not.
Arborback Stomper: The life gain will be good in Limited, I guess. Otherwise, a solid uncommon, yet not special.
Armorcraft Judge: Oh, here is my Johnny card. I love these cards. Now I want to build a deck where every creature gets counters, and then I want to draw a ton of cards off of this card. Great Johnny uncommon.
Bristling Hydra: Because every set has a Hydra. It does not get outrageously big like some of the better Hydras. It seems destined to be a junk rare.
Attune with Aether: Good enough with the land draw, and the Energy gain is a nice bonus.
Blossoming Defense: Reads like a Limited common. Compare with Giant Growth. Hexproof can only go so far, and is useless if your creature is not about to be the victim of targeted removal.
Commencement of Festivities: A weaker Fog, fitting of battlecruiser Magic. Stronger than Fog in some multiplayer situations, especially if you are in a team like Two Headed Giant (2HG).
Cowl Prowler: Limited vanilla creature. Someday there will be a Vanilla-matters deck, and this card will want to be in it.
Cultivator of Blades: It wants to be enchanted for counters, maybe with equipment. It reads like a Johnny rare and I like it. It doesn't make sense to make the tokens given the attacking triggered ability.
Creeping Mold: Old-school reprint. A solid inclusion.
Dubious Challenge: Long text here. OK, you have your top ten cards, say there's four creatures. You pick two of those creatures, and your opponent chooses one of those for himself, then you get to play the remaining one. I don't see how these choices could benefit the person playing this card. Your opponent can choose the best creature. I guess if you are playing a tribe that your opponent is not, they have nothing to gain from, say, getting a good elf from your deck. I will need to see this in play. Right now, it reads like a junk rare.
Durable Handicraft: Oh, I want this bad. This is my way to get counters on all of my creatures. I am in.
Longtusk Cub: Make it unblockable somehow, and profit for Energy all game long. Solid uncommon.
Elegant Edgecrafters: Reads like a Limited uncommon. It's a 6 mana 5/6.
Nature's Way: Trample is great. You pit your big Green creature against something small, kill it, and then deal the remaining damage to your opponent. Nice!
Fairgrounds Trumpeteer: Fits like a glove in the 'counters on all creatures' deck. I want it.
Highspire Artisan: Interesting for Limited.
Ghirapur Guide: Good to get past Walls. Reads like an useful uncommon. And it's an elf.
Hunt the Weak: nice reprint for Limited.
Kujar Seedsculptor: useful in Limited.
Nissa, Vital Force: The +1 is strong. A 5/5 creature is good, even though Nissa is coming in turns 5 or 6 in Standard. The -3 is really good because permanent can mean many types of cards. The ultimate is sweet, but not immediately game breaking. However, the ultimate can be attained with relative ease when compared to other planeswalkers. If you +1 when it enters, you can ultimate next turn and lose this card, or wait another turn if no one dings it.
Larger than Life: sweet buffing in any format at a reasonable cost. It's a Sorcery, and that is a limitation because you cannot use it after blockers have been declared. It will be good in Standard. In Modern, you want to play this effect at Instant speed even if you have to settle for +3/+3 in that other format.
Ornamental Courage: A defensive Limited jank card.
Oviya Pashiri, Sage Lifecrafter: Solid incremental rare. The cost for a Servo token is a bit high, and the X/X token can be a dud if you don't control that many creatures. It takes a lot of setting up, yet it's in the tradition of really powerful cards that offer similar versatility. Figure of Destiny is a good example of this type of card.
Riparian Tiger: Limited jank.
Peema Outrider: Limited jank.
Sage of Shaila's Claim: Limit jank with an Energy bonus.
Wily Bandar: mid game versatility with the indestructible clause. I like it. It makes me miss mana dorks, though.
Servant of the Conduit: Speak of the devil, we lost Green one drop mana dorks, which are awesome, for two-drop 'any color' mana dorks. The Energy here will be well spent, but what I really want is a one-drop mana dork for mono-Green.
Take Down: Versatile one drop. It's great against flying 1/1 tokens. In Green/Black it can trigger lots of Blood Artist triggers. You are probably wondering about why I keep mentioning Blood Artist. It's because someday I hope to have a deck built around it in Modern, Legacy and Vintage that is a real winner. We are not there yet.
Wild Wanderer: Limited jank. The land is a great benefit, but it's a four drop. You want this effect earlier to prevent early game mana screw.
Thriving Rhino: Limited jank and a card I plan to use to understand the Energy economy.
Wildest Dreams: Let's see, if X is 3, this is a 7 drop to return three cards from your graveyard to your hand. The effect is much cheaper in Black. I think this is a junk rare.
Verdurous Gearhulk: That's very useful, and does not feel Mythic. Compare with Primeval Titan (Trample Whenever Primeval Titan enters the battlefield or attacks, you may search your library for up to two land cards, put them onto the battlefield tapped, then shuffle your library.) Primeval Titan feels Mythic and is a Modern staple. This card is more in line with the plane-named Mythics from Magic 2015, such as Soul of Zendikar. But even those felt more Mythic than this card.