I remember seeing this thread a couple years ago when Renaissance was new, and had an idea involving Priest and Capitalism. So with a hand of some ratio of black markets to priests, you'd first play a BM to get a ton of silver, then trash it all to priests. Then, you can nest a chain of all the remaining black markets you have, then for each one you can buy the doctor and get a ton of money back from all the priests, as well as a ton of silver, the money from which is negligible compared to the money from preists.
Storeroom wouldn't work with capitalism, however I believe the only issue with nonterminals is Golem, so removing that allows the use of something like a bunch of Warehouses to discard all the silver we end up with into more black markets and priests. This can only be done outside of a black market, meaning the next one does cost an action. (edit: a Cellar would be a simpler way of doing it)
Then, Conclaves could also be used inside black markets to play almost every card in the game that isn't a village or nonterminal draw.
How much money/gains can this make?
Well, say you have played P priests this turn, have a chain of B black markets deep, and M money.
Each doctor buy trashes M-3 rocks, gaining (2*P+2)*(M-3) money total (from priests and silvers), which can be approximated as 2*P*M when the numbers are large enough. (or simply using a cost reducer to make doctor cost 0; and treating P as number of preists + 1 instead, to make the approximation exact). Repeating this B times gets you (2*P)^B * M total money, and approximately that many cards in hand too.
Using 1 action cycles away the hand into mostly black markets (as increasing the exponent does a lot more than increasing the base), thus replacing B with (something greater than) (2P)^B. With A actions, this nets you (2P)^^A, where ^^ represents 2 arrows of
Knuth's Up Arrow Notation.
So (2P)^^A approximates the number of cards in hand, which in turn approximates the amount of money available at the end, which in turn approximates the final number of gains.
A can be made so be somewhere in the hundreds thanks to Conclave.
