To your credit, the cards in your "Completely Tested" section look well-balanced (except Abandoned Village). I'm not in love with most of these cards just because they're a bit too vanilla for my taste, but you indicate in your comments that you love vanilla cards, so it's understandable.
Completely TestedAbandoned Village
Action-Reaction: $4
+1 Card
+2 Actions
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When a player gains a victory card, you may set this aside from your hand. If you do, gain a Silver, putting it into your hand. Return this to your hand at the start of your next turn.
I wanted a village that was a reaction, and I wanted more cards that gain silver to be in Dominion. I decided to combine the ideas, making a village that can be used to generate money lategame, when your engine begins to stall out.
I guess "gain a Silver into hand" is probably sufficiently different from Beggar's reaction. And of course it reacts to a different trigger. The fact that you also effectively keep your Abandoned Village in hand makes it quite powerful. I think maybe the fact that this reacts to
any Victory card gain might be too much. It's basically [+1 Card; +2 Actions; +$2; Gain a Silver] if any of your opponents gained a Victory card. That's incredibly good. Perhaps just gaining or topdecking the Silver might be better, but maybe those would be too weak. For what it's worth, you'd usually be drawing a topdecked Silver with the Abandoned Village itself, which may or may not be desirable depending on the circumstances.
Bath House
Action: $4
+1 Action
+1 Buy
+$1
Trash 1 or 3 cards from your hand.
Trash 1 or 3? Originally, the card said 'up to 3' but that was too lenient. A basic trasher that has been tweaked over time. Since often people like to trash 2 cards, the 1 or 3 mechanic makes this an interesting card to play.
Huh. I'm not super captivated by the "1 or 3" mechanic, but it is unique, I'll give you that. It seems like it would just be adding swinginess for the sake of it, though. If you have 3 cards you want to trash, yippee! If you only have 2 (and at least one card in hand you don't want to trash), then you can only trash one of them, grumble grumble. But without that mechanic this is basically a retread and either way it's very close to Forager.
Archer
Action: $4
+2 Cards
+1 Buy
+$1
Discard a card.
I really, really, really like vanilla cards, and I knew there was still room for some in Dominion. Hence this card. The 'discard a card' was added after it was found to be too powerful for $4 but too weak for $5.
Well, this is a very vanilla card. It doesn't really excite me, but then again it's a vanilla card. So, yeah. Looks balanced.
Missionary
Action-Reaction: $2
Trash 2 cards from your hand.
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When you would gain a card, you may discard this from your hand. If you do, instead gain a card costing exactly $1 more.
Some of you might know this from the fan cards set contest. I wanted a weak trasher that could turn into a treasure later game, and after a while, I turned the 'treasure' part of it into a reaction.
I like the top half for a cheap Reaction like this. This reaction used to rub me the wrong way, but I think I'm warming up to it a bit. It's cool when you're using the reaction on a card you're gaining during your Action phase or on someone else's turn, but during your Buy phase it's an extremely convoluted Copper that you can't, for instance, use to buy a Province when there is no $7 card in the Supply.
Scribe
Action: $2
+1 Cards
+1 Action
Name a card costing $5 or less. While this is in play, when you gain the named card, put it on top of your deck.
Well, not all $2 cards are amazing. This one stays because it has potential use in speeding up engine/combo decks.
At first I thought this was too much of a retread of Watchtower and Royal Seal. It is close to Watchtower, but I think it'll probably play differently enough to be interesting. Why are you limiting it to cards costing up to $5? You don't usually want to topdeck Provinces and topdecking Golds seems fine. In the games where you have $7 cards and Platinums, that's just a cool combo. You often won't know whether you'll be able to afford a specific expensive card when you play the Scribe anyway.
Also, I don't think Dominion's rules even allow you to qualify "Name a card" with things like "costing up to $5". When you name a card, you're just saying one or more words that may not even be a real Dominion card. The information about whether you named a real card and whether it currently costs $5 or less may not be available.
Panacea
Action: $3p
+1 Card
+1 Action
Choose one: +1 Card; or +$1, +1 Buy; or trash a card from your hand.
Another one of my cards that placed in the fan card set contest. I wanted versatility, but little complexity. Kind of has an intrigue-esque flavor to it.
Thinking about the different options, I can see the utility of the card. But when it comes right down to it, it's a collection of vanilla bonuses, which rarely excites me. Especially on a new Potion-cost card, I usually want something more unique. Again, probably fine at this cost.
Partially TestedAssassin
Action-Attack: $5
+$1
Put your deck into your discard pile. Each other player gains a curse.
I wanted a curser that could be played often, but offered little benefit to the person playing it. It's fairly strong in engine decks, hurting the other players and marginally accelerating your own deck.
At first I thought this seemed really weak. It might be. But probably it's quite good
as long as you're the only one playing it. If other players are playing it, putting your deck into your discard pile is much less desirable because you'll be shuffling in some fresh Curses along with the cards you're buying. And of course you usually won't be the sole player playing a cursing attack.
Canal
Action: $3
+1 Card
+1 Action
You may discard a card costing $4 or less that is not a victory card. If you do, gain a copy of it.
My friend's creation, this card can sacrifice being able to play something from your hand on the current turn, for a later game benefit.
I had a similar card at one point that didn't have a cost cap but also was a terminal. As a cantrip, this looks potentially very powerful for running out cheap piles very quickly. Especially since it can gain itself. But then again you're reducing your handsize as you copy cards. So probably it's fine.
Cathedral
Victory: $3+
2vp
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When you buy this, you may overpay for it. When you buy this, gain a card costing up to $2 less than you paid for this.
Designed before Guilds came out. I wanted a new mechanic to use in a few cards for the set. This is the only one that has stuck
This is basically just a card worth 2 VP that you can gain by paying an extra $2 whenever you buy a card costing at least $1. I guess it might be balanced. I can't say I find it that interesting. Stonemason just does this way better.
Sneak
Action: $3
+2 Actions
+$1
Each other player reveals their hand. If and cards costing $6 or more were revealed this way, +$1, +1 Buy
Designed to be slightly more powerful in 3-4 player games, it's a weak +Action card that can act as a cheap festival lategame.
The trigger is often automatically going to fire in the late game. I feel that if you're going to have a card that fires under certain circumstances (like Menagerie, Tournament, etc.), then you should have some control over how likely it is to fire. That way you have incentive to build your deck a certain way. Even with City you have some control over how much they upgrade and when. With Sneak it's all up to your opponents.
Tribute is different in that you're getting different bonuses depending on the other player's deck. Here it's the difference between a crappy effect and a good effect. I find that less compelling.
Prospector
Action: $5
Trash a card from your hand. Choose one: +$2; or draw until you have 5 cards in hand.
This card was designed to counter Assassin, and functions fairly nicely as a trasher.
I like this. At first it seemed a bit weak for $5, but I think +$2 option is probably a good $4/weak $5, and the draw up to 5 cards option likewise. Put the two together and you have a neat little versatile $5 card. Very nice!
UntestedTailor
Action: $2
+2 Cards
When you gain or play this, you may shuffle a card from your discard pile into your deck.
A recent idea. No clue how it should work.
I think this would be fine as an online card. In real life, that's
way too much shuffling.
Untitled1
Action-Attack-Reaction: $5
Gain a coin token.
You may pay a coin token. If you do, each other player gains a curse.
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When another player plays an attack card, you may discard this. If you do, take 2 coin tokens.
A recent idea, inspired by guilds.
This seems almost certainly too weak. It's basically either [Take a Coin token] or [Each other player gains a Curse]. The first is weaker than Candlestick Maker. The second is weaker than Sea Hag. It's not that I'd never ever buy it at $5, but it compares really poorly to other Curse-giving cards at that price point. I do like how it helps your deck more after the Curses run out. Even if you buff the card, I'd keep that mechanic.
The fact that the Reaction is there boosts the card, but not enough to cost $5. It seems like an obvious reaction effect, and I was a bit surprised that Guilds didn't have such a Reaction. I doubt a Reaction that you have to discard is going to be used on a curser until the Curses are gone (unless you collide two of them and are happy to discard one). So I'm not sure this Action is a great fit for the Reaction.
Old Archives
Action-Duration: $2
+1 Action
Set aside the top 4 cards of your deck.
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At the start of your next turn, return the set aside cards to your hand, then discard 4 cards, then trash this card.
A one-shot better-than-Warehouse duration. Basically.
Interesting idea. At $2, I might pick one up. If it's too weak, I recommend adding either +1 Card or +$1 to the "this turn" portion. Also, you shouldn't have a line between the "this turn" part and the "next turn" part. They are both things that happen because you played the card.