Woo, I missed a bunch of the responses, sorry, will try to catch up. Thank you all for you comments!
I might need to do a "secret history of" at some point. It's been suggested, and I'm a narcissist, so why not?
First off let me clear up a misconception on Tomb Raider. Tomb Raider only ever lets you gain one card per turn. So in ClouduHieh's example of the double-Tomb Raider turn, on the second time your play Tomb Raider, when player 3 reveals Harem and player 4 reveals Gold, you are going to need to choose whether you want a Harem or a Gold, and pick that one. Perhaps I need to slightly adjust the text to make this more obvious (e.g., You gain a copy of one Treasure revealed this way.)
Grave Watcher, this is sort of a janky card for sure, but I do like it. If there was one thing I would change it would be to rethink the curse yourself, but really the set is done except for proofreading, plus if something is totally broken. I ran a WIP thread for months. That was the place to argue about design. But don't think I'm not listening and taking things to heart, even if I sound grumpy about it. Grave Watcher is all about presenting the player with a bad decision. Do you make it non-terminal? Do you move yourself from $7 in hand to $8? But don't let it go to your head, it's going to lose you the game if you're not careful. This thing could have been "mephistopheles" or "infernal contract" except then it was in too much danger of being clobbered by Nocturne (Nocturne was coming out when I was working on it.)
Then the attack; the attack was shoehorned in for two reasons. One, I realized I didn't have enough attacks in the game. Two, at one point this card was called "Pixiu", a Chinese dog/dragon thing that guards money and brings financial luck. So I gave it a financial luck attack. The attack rarely happens though, so it can be obnoxious but it isn't super obnoxious. As it is though, you never want to buy Grave Watchers for the attack, you buy them for the flexibility to make bad decisions. It turns out that Antiquities ends up having a whole bunch of attacks that can miss; it's almost worth saying that it's a theme of the set.
Collector, there's a weird thing that happens when you do designs. Sometimes a card that is bad gets popular with a certain segment of the fanbase. In this case, my fanbase is very small (20 people? that might be generous) and the segment of the fanbase is my wife. Since she is the person who I will play these cards with the most, her opinion matters. Anyways originally it had only the bottom rule, no looking at the top card. Also it would dump the gained card into your discard pile, so you'd really lose all the time, since you couldn't play it. So she would play this card every time she could and it would just tank her game. It was terrible. But she still used it every time. So eventually I buffed it to put the card back where you found it, which normally means you are at least breaking even every time you use it. Even then it still wasn't worth her focus. The randomness was just too, you know, random. At the same time I was reading every single entry in the Interview with Donald X for design insights to make the set better, plus more authentic, and realized I was lacking in "non-attack interactions" so I decided to add the top. If the testing still meant the card was bad all the time, I could increase the number of cards you scry before doing the random upgrade. But it appears that one is just fine. By the time I was doing all this, I had already ordered the art. If I hadn't, I would have renamed the card to "Gambler", since ClouduHieh is totally right, it's almost a total gamble.
Riches has a huge page of opinions (mostly that it is broken OP) in the WIP thread, but my testing didn't line up to the allegations that it is broken. I've never had it run away with a game yet. Eventually some players started pointing out that it's hard to use in a broken way. I'm not going to defend it though, just go read the WIP thread. But, again, like I said on reddit, the problem with my test group is that we're probably B or C-tier players. A and S tier players may be able to single-handedly use this card to go insane things. At least in Dominion a card is always available to everyone to use, as long as it doesn't become the only strategy that makes any sense every time it appears.
I am going to modify the rules to make it more obvious that having 2 Riches in play means you just blew up both Riches, though.
Thanks so much for the attention and respect you're giving this set, though! I always hope I don't sound too dismissive. I appreciate all of it, criticism included!