It's as I feared: Many of the Hinterlands card submissions ended being just convoluted, not cohesive, or just strange. This was definitely a harder set to design for than Prosperity.
Some thoughts on a few cards.
Tribe
Types: Action
Cost: $3
+2 Actions. +$1. Look at the top 2 cards of your deck. Discard one and put the other anywhere in your deck.
When you buy this, you may discard a card. If you do, +1 Buy and +$2.
Of the +buy on-buy cards, this one seems the least likely to get out of hand. You have to discard a card to get the effect, so it's not an endless loop kind of thing. Unfortunately, this gets out of hand with a single Highway (a Hinterlands card) in play!
Quagmire
Types: Victory
Cost: $3
Worth 1 VP.
When you gain this, trash 3 cards from a Supply pile.
Even with a no-victory card clause for the bottom, Dark Ages cards break this ability.
Hinterland
Types: Action
Cost: $4
Swap the cards in your hand with the cards on your Hinterland mat.
When you gain this, gain a Silver, putting it on your Hinterland mat.
Okay, there is a bunch talk about this card. I'll admit it's one the really unique submissions here, though it compares to Native Village. If any kind card form here belongs in Seaside, it's this one. I'd like to see a variation of this later on in the contest. As written, It just seems silly.
Pilgrimage
Types: Action
Cost: $3
+1 Action. +2 Buys.
While this is in play, when you gain a Victory card, Victory cards cost $1 less this turn, but not less than $0.
Clarification: Buying this multiple times in a turn does reduce costs each time.
What's up with the clarification here? Why would buying this reduce costs? Uh, seems too strong in the presence of gainers. One Stonemason that gives you 2 Estates makes Estates free during your buy phase.
Mountain Dwellers
Types: Action
Cost: $5
+1 Card. +1 Action. Reveal your hand. If you revealed 3 or more Treasure cards, +$1.
When you buy this, you may trash a Treasure card you have in play. Gain a Treasure card costing exactly $3 more than it.
I like the concept, and I'm curious to see how strong it is. It can turn a Silver into a Gold for only $5, but I think you need to reliably activate the peddler on-play effect to make it truly effective. I think what it really needs is some sort of first-game engine.
Troglodyte Caves
Types: Action
Cost: $5
+1 Card. +1 Action. Discard any number of cards. +1 Card per card discarded.
When you gain this, you may reveal a card from your hand costing less than this. Gain a copy of it.
I like this one too. I noticed the "less that this" clause, Which helps with a bunch of balance issues. I don't mind that it's similar to Cartographer. We haven't seen a Cellar variant that doesn't reduce handsize yet.
Vendor
Types: Action
Cost: $1
+1 Action
When you buy this, +2 Buys.
Don't remember if I talked about this one yet, but seriously. I have 1 Highway and a couple of Goons in play. Mega ownage.
Artefact
Types: Action
Cost: $2
+1 Card. +1 Action. Choose a card from your hand. Trash it, discard it, or put it on top of your deck.
When you buy this, set it aside instead of gaining it. Discard it after you next shuffle your discard pile (or when the game ends).
We should give this one a chance. Cantrip trashing is really strong, but this misses a shuffle. But then, if I open Nomad Camp...
Ring Leader
Types: Action – Attack
Cost: $3
+2 Cards.
When you buy or play this, each player (including you) reveals the top 4 card of his deck, discards one that you choose, and puts the rest back in an order he chooses.
A good Spy effect, if such a thing exists. Sure, there is some AP involved, but this is terminal and actually has a good chance of being effective.
River
Types: Victory
Cost: $3
Worth 2 VP.
When you gain this during your turn, all cards except Victory cards cost $2 less this turn, but not less than $0.
I notice the anti-synergy with itself and the on-gain effect. Worth a closer look.
Factory
Types: Action – Reaction
Cost: $4
+1 Action. You may discard a card that is not a Victory card. If you do, gain a copy of it.
When you gain a card, you may reveal this from your hand and put it onto your deck. If you do, put the gained card into your hand.
That on-gain effect is new, and I like it. But the on-play...that's something that should be on-gain, or on a terminal action.
Sanctuary
Types: Action
Cost: $5
+2 Cards. Discard 2 cards.
When you gain this, set aside a card from your hand. Return that card to your deck at the end of the game.
I like the allusion to both Island and Oasis in the name (am I missing one?). This compares unfavourably to Inn, I'm afraid
Workers' Co-operative
Types: Action
Cost: $5
+1 Buy. +$3.
While this is in play, when you buy a card, each other player may gain a card costing less than it.
I don't think people realize just how much benefit this kind of thing is for your opponents. The 3-pile problem is especially relevant in multiplayer games. But as it's been pointed out, Contraband also has a pretty big penalty, so perhaps it fills a very specialized role. Must it be terminal?
Smelter
Types: Action
Cost: $4
+1 Buy. +$1.
While this is in play, when you buy a card, gain a Silver, putting it on top of your deck.
I'm for this card. using 4 buys gets you a Province next turn, and all those Silvers help you get at least one Province in subsequent turns. I like this silver flooder with Gambit potential.
Witch Doctor
Types: Action
Cost: $4
+$1. Look through your deck; reveal and discard any number of Victory and Curse cards from it. Shuffle your deck.
When you gain this, put your deck into your discard pile.
If you expect your card to be well received, you should distance your card from the stupidly swingy Chancellor and Counting House as much as possible.
Diviner
Types: Action
Cost: $3
+2 Cards. +1 Buy.
While this is in play, when you buy a card, reveal the top 2 cards of your deck, discard any number, and put the rest back on top in any order.
Reminds me of Scouting Party from the Dominion Outtakes, but this only applies to one player, so it's not such a mess in the end. This fits Seaside much better than Hinterlands, though.
Mill
Types: Action
Cost: $5
+1 Action. Each other player draws a card. Gain a card costing up to $5.
When you gain this, each other player discards down to 3 cards in hand.
It's been mentioned that this is awful for the game when p1 opens 5/2, especially since this card is actually powerful.
Courier (A)
Types: Action – Reaction
Cost: $4
+1 Card. +1 Action. Discard any number of cards. Gain a card costing exactly $1 per card discarded.
When you would gain a card other than during your Buy phase, you may discard this from your hand. If you do, gain a card costing up to $2 more instead.
I like cards that benefit large handsizes. Weak with the top-only effect, but the bottom effect makes up for that, I think
Oicho-Kabu
Types: Action – Victory
Cost: $5
+1 Buy. +$2.
Worth 1 VP. While this is in play, when you buy a card, +$2 and discard the top card of your deck. If it's a Victory card, trash this.
This gets trashed if it turns over a copy of itself, so no, not that broken. I might even vote for it.
Wayfarer (A)
Types: Action
Cost: $2
+1 Card. +1 Action. +1 Buy.
When you buy this, you may trash a card from your hand. If you do, +$ equal to its cost in coins.
Yes. Cool. Salvager in a pinch. Now this feels more like Hinterlands.
Safe House
Types: Victory – Reaction
Cost: $3
Worth 2 VP.
When you gain a card costing $0, you may discard this. If you do, gain a Gold.
Powerful, but implemented as a reaction that has this card discarded. I don't see what's wrong with it, and I might make for less dreadful games in the end.
Clairvoyant
Types: Action
Cost: $3
+1 Action. Look at the top card of your deck. You may put it into your hand. Otherwise, +$1 and either discard it or put it back. Look through your discard pile and put a card from it or your hand at the bottom of your deck.
Barring Pearl Diver, I expect the bottom-of-the-deck thing will be best for junk cards that you want to miss the reshuffle.
You know, sometimes simple and concise is better.
Fence
Types: Action
Cost: $5
While this is in play, when you buy a card, gain a card costing exactly $1 more than it.
Though it looks like a worse Haggler, it's at least better for gaining cards at the $2 and $3 price range. I'm sure it can be rebalanced if needed. The real question is if Haggler makes it superfluous.
Thrift Shop
Types: Action
Cost: $6
+1 Action. +$2. If this is not the first time you played Thrift Shop this turn, you may gain a card from the Thrift Shop mat.
When you gain or play this, place a card costing up to $5 from the Supply onto the Thrift Shop mat.
Clarification: There is only one community Thrift Shop mat. Each player does not have his own.
The issue with this card is that you'll be discouraged to get these if your opponent already has a few because the placing of a card onto the mat isn't optional.
Chapterhouse
Types: Action
Cost: $5
+1 Action. +$1. Draw until you have 6 cards in hand. Discard 2 cards.
When you buy this, each other player draws a card. When you gain this, each other player with at least 4 cards in hand discards a card.
The top part is cool. The bottom part has potential. Both parts have a draw-and-discard theme. Overall, it's nice, I guess.
Barn
Types: Action
Cost: $5
+1 Card. +1 Action. Discard a card. If you discarded a Victory or Curse card, gain a Treasure costing up to $4. Otherwise, +$1 and gain a Victory card costing up to $4. Put the gained card into your hand.
When you buy this, gain an Action card costing up to $4, putting it onto your deck.
A bunch of Workshop variants, and this one possibly has the most charm. You can't gain Schemes or other actions with it, but it's a cantrip so it's just as well that it doesn't. Silk Roads are fair game for this. Tricky to use right, but I approve.
Wagon Raider
Types: Action – Attack
Cost: $4
Each other player may put a card costing more than $2 from their hand into your discard pile. If he doesn't, he gains a Curse.
While this is in play, when you buy a Gold, you may gain a Province instead.
It's become apparent that it's really a no-brainer to take the curse. Unlike Cultist and Torturer, this doesn't draw, so there's little risk of being flooded with curses. With the "instead" change, this should just make Provinces worth $2 less, no?
Nomadic Village
Types: Action – Reaction
Cost: $4
+1 Card. +2 Actions.
When you gain this, put it into your hand.
When an opponent gains an Action card, you may discard this. If you do, search your discard pile for an Action card and put it into your hand.
Weirdly enough, I prefer this without the reaction bit, only because it would belong below a separate line. Or the on-gain can be removed. Either way makes this better.
Stranger
Types: Action
Cost: $5
+1 Card. +1 Action. +1 Buy. Each other player discards the top card of his deck. Copies of cards revealed this way cost $2 less this turn, but not less than $0.
This scales so much with the number of players. It's a cantrip on top of that. This can't possibly work as a cantrip.
Courier (B)
Types: Action
Cost: $2
+1 Action. +1 Buy.
When you discard this from play, if you bought no more than one card this turn, you may put this on top of your deck.
Maybe this is bland, but it would have been a great addition to Hinterlands. Keep in mind that, unlike Walled Village, this doesn't have anti-synergy with itself. So you will eventually get the +buy when you need it, at the cost of 1 spot in your hand.
Pyramid
Types: Action
Cost: $4
+1 Action. +$1. +1 Card per Pyramid you have in play. Discard one card per Pyramid you have in play.
When you buy this, gain an extra copy of it.
I like how this card works, but I actually think this is too powerful at $4.
Lucky Coin
Type: Treasure
Cost: $4
Worth $1.
When you gain this, each other player with at least 5 cards in hand reveals his hand and discards a card that you choose.
Why are people so against this card? At least this should be fine balance-wise. It's not like Mill above, where the card's on-play is actually good and getting it denies others from getting Mill. This sucks once in your deck, and it only costs $4. If anything, this saves someone with a 3/4 split from losing horribly to Mountebank/Chapel or something. I have no issues against it.
Used Land Salesman
Types: Action
Cost: $5
+4 Cards.
While this is in play, when you buy a card, gain a Victory cards costing less than it.
Now I'm wondering about how decent of a nerf the forced vicoty card gain is. It still looks too strong on board with hybrid victory cards, Crossroads, or Silk Road.
Wayfarer (B)
Types: Action
Cost: $4
Reveal cards from your deck until you reveal one costing $1 or more. Put all the revealed cards into your hand.
When you discard this from play, gain a card costing up to $1 per Copper you have in play.
This opens up a new copper-based strategy. The effect below the line is what elevates this to nifty/cool/interesting territory.