A few observations:
Petroglyph (4)
Action - Reaction
+1 Action
Discard any number of cards, then draw until you have 5 cards in hand.
-
When you discard this card any time other than during Clean-up, you can reveal it and set it aside.
If you do, discard it at the start of your next turn and draw a Card.
The way the wording on the reaction part reads, when you discard it from setting it aside, it can still be seen as discarding other than during cleanup and you could choose to set it aside again. This can be a nifty choice you can make, if you draw a good hand and don't need the extra card. You could even stock them up and draw several cards at once for a mega turn. It's a nice feature, I just wonder if it was intended.
Obelisk (5)
Action - Reaction - Attack
+2 Cards
You may trash two differently named cards from your hand. If you do, +[VP per $2 one of them costs.
-
When you discard this card any time other than during Clean-up, you can reveal it. If you do, each other player gains a Curse.
Agree with the comments made on the reaction part. The top part alone looks strong compared to Bishop, with the card draw as well, but the trashing two different cards may be enough of a setback. Either way, you'll need to say '(round down)' for odd-number costs.
Tomb Raider (4)
Action
+1 Action
Each opponent discards an attack card (or reveals a hand containing no attacks.)
You may gain a copy of a Treasure revealed this way.
Maybe have them reveal their hand regardless? In games with no attacks this seems to just be Ruined Village. I guess this needs the Attack type anyway, to help here, so like this:
Tomb Raider (4)
Action Attack
+1 Action
Each opponent reveals his hand and discards an Attack card.
You may gain a copy of a Treasure revealed this way.
Edited:
(But then if this is the only Attack in a game, will it ever be bought?) It can become a lesser Hero in gaining any treasure, which is fine, it just runs the risk of clashing with the opponent's Tomb Raider.
Idol (4)
Treasure
$3
While this is in play, when you buy a card, put it on your Idol mat.
If it a Curse, start a new turn with all of the cards from your Idol mat as your hand.
Wording advice on this would be appreciated.
An interesting card. Just to make it more like Outpost's wording:
While this is in play, when you buy a card, put it on your Idol mat.
If it is a Curse, take another turn after this one, with all of the cards from your Idol mat as your hand.
And I don't suppose it needs to let you only take one extra turn. I don't think you can take infinite turns with it as you're forced to buy another Idol and Curse, and no one action can give enough buys and $. Well, with Ferry and Seaway it might be possible...but it only ends the game on 3 piles with you on numerous Curses, so all good.
Inspector (3)
Action - Attack
+2 Cards
Reveal then discard 2 cards.
Per card discarded, each other player with 4 or more cards in hand dicards a copy of it (or reveals a hand with no copies.)
I assume you reveal from your hand?
Riches (4)
Treasure
$4
When you buy a card using this, trash all the other treasures you used to buy that card.
I like the potential in this one. So you only buy one, and this ultimately becomes the only Treasure in the deck, and so it sets up engines. I think it needs virtual coin to work rather than make it OP, as other Treasures are almost worthless as one-shots (buy a gold for 6, it pays back only half of that). I have two questions with this: is 4 the right price for it? You can easily get a 5-8 cost card by turn 4, and trash some coppers at the same time. Which leads to, how do you declare what Treasures you use to pay for cards? Suppose I have a hand of Riches and 3 Coppers and want to buy a 4 cost card. Can I declare paying the three Coppers on it, perhaps by playing them first, or would the Riches always be the whole cost?
Collector (4)
Action
+$2
Reveal and trash the top card of your deck to gain a card that shares a type with it that costs up to $3 more.
Mine deals exclusively with Treasures and costs 5. Rebuild does Victories and is 5, and Expand is 7. I doubt the randomness and same-type restriction reduces the cost that much, especially as it doesn't interfere with your hand.
Ziggurat (4)
Action
You may discard cards from the top of your deck until there are 3 cards in your discard pile.
You may trash up to two cards from your discard pile.
If you trashed a card, you may play a card from your discard pile.
Can it play a Treasure? Could you bring an Estate or another pure Victory into play to Bonfire it?