Fun exercise: Enumerate every way you can think of to make a deck Golden.
Definition: A Golden Deck is a deck that achieves its intended purpose reliably, every turn, and fundamentally cannot stall.
Worth noting is that any deck that buys VP cards for points must be able to do something about them. Even if an engine can kick off with any one action card, if there is even the remotest possibility of drawing five VP cards to start the next turn, that's not Golden. It's just "reliable."
(The Classic: Bishop/Money/VP, trashing a single VP card for tokens every turn, rebuying.)
Hand reliability techniques:
-- Junking down to a 5-card deck (Chapel/Donate/etc.)
-- Having a deck of any size containing no more than 4 stop cards.
Stop cards include all terminals, treasure, VP, or non-drawing splitters. In addition to cantrips and non-terminal draw, Action-fixers like Champion/Lost Arts/Teacher can turn decks golden in an instant.
-- Starting each turn with a hand size greater than 5
Duration-draw, such as Tactician, Haunted Woods, Enchantress. Prince. Even Summon can do the trick. Also noteworthy are Gear/Archive/Haven. Also Expedition.
-- End-of-turn deck stacking
You may be able to turn a deck golden with topdecking. This includes the classic Scavenger/Stash, but also Secret Passage, Scheme, etc. This could completely and utterly prevent any possibility of stalling even if the deck contained 6 stop cards, for example, by ensuring that the top of the deck was guaranteed to grow your hand to 7 cards with an action to spare.
Points reliability techniques:
What to do about greening so that the deck doesn't turn from gold to lead while you buy VP cards?
-- VP token strategies. (Duh. Goons/Groundskeeper/Watchtower/etc. Multi-Monument, Just about Everything from Empires...)
-- Setting VP cards aside.
Island, Native Village, and arguably, Archive/Gear/Haven if carefully managed.
-- Sifting?
Sort of. If you can guarantee a minimum starting hand size, each sifter in a Golden Deck can "spend" VP cards for extra draw, but you still can't expand your VP cards beyond your guaranteed minimum starting hand size - 1.
Attack vulnerability:
Attacks often destroy Golden Decks, but there may be exceptions. Some can play three-card hands or four-card hands, making Discard attacks irrelevant, possibly including Minion. Some can play trashers every turn, making junking attacks irrelevant. Note that Prince and duration draw resist discard, but Expedition does not. Trashing attacks and/or topdeck attacks can also spoil a Golden Deck, but could possibly be mitigated by gainers.