Not sure if this was already known, but donald posted in the new forum saying this about the adventures:
So, back when, Goko - which to some degree consisted of different people - had the hope of making money off of the campaigns by getting people to buy zaps (this contradicts what the FAQ says, which is wrong, and man I would know). This was a bad idea that wouldn't work anyway and I gradually convinced them of that. They gave up on it but were busy doing other things. So there are still those zaps and these stupid levels you can't possibly beat without endlessly zapping. They are awful.
They wanted me to put work into fixing up the campaigns and I did. I'm a sucker, what can I say.
The plan is to get rid of the zaps, which just suck the joy out of those games, and add little touches that make things more interesting. In act 3 you will typically have a rule that modifies the game in some exciting way; they were programmed and I tested them, in an off-site version, as if yes they would really be used someday. Some games will vary the starting hands in some interesting way, but none of them do the stupid thing that's currently there. I also overhauled the main set sets-of-10, including sprinkling in expansion cards, so that those games wouldn't get too repetitive.
Last I heard this was still the plan, that work was not going to be wasted. Until they either fix the campaigns or say "no we are keeping the bad campaigns lol," I would put off playing the campaigns. Someday they might be fun, why not wait for that. You don't need the promos just yet. And if they never fix them, I sure wouldn't grind through them.
If you are desperate to get at least one promo, you can play the first few levels of each campaign act 1, before it starts giving the bots 3 Provinces to start. Dark Ages Act 3 was changed to fit an intermediate plan but the other acts weren't; you can play through that act on your two free zaps, since it only goes up to Silver/Province/Duchy and the two-Duchy lead is beatable. And then while Prosperity Act 1 is crazy, you can actually beat most levels with good play, largely on the back of VP tokens.
I gotta say, I find the prospect of rules that modify the game in an exciting way to be, well, exciting! It's cool that even though we may not be seeing many new Kingdom cards, there may still be new Dominion experiences to be had. I would love to see the option of turning on these rules in multiplayer games as well, if they lend themselves to that.
I remember that at one time there were going to be card-specific achievements. I'd love to see those as well. Finally, I hope Goko decides to implement the online-specific promo card that Donald offered them
last October. Assuming they're going to attempt to implement the new physical promo, they could do both of them at once.