Dunno if its been mentioned.
Watchtower/Squire
Buy squire, reveal Watchtower, trash Squire, gain attack, reveal Watchtower, place attack on top of deck. Not to mention that apart from the trash it's a village that decreases handsome that gives cash.
It's kinda a big deal.
Yeah that's a good one, especially if goons happens to be out
I know Watchtower is well regarded and all, but I still think it is underplayed (at least on Goko where I play my games) because it is hard for players to remember all of the possible interactions it could have with the rest of the board.
For example, King Zog said that watchtower's top deck ability doesn't interact with treasure map, but it does if you can acquire two in a turn. There are many ways to do this, one of which is in my OP
Watchtower is the only card that surprises me, that is to say, it gives me benefits that I didn't anticipate when buying it.
Also some players overestimate the difficulty of building an engine with watchtower. Yes, Library is certainly better, but there are plenty of situations where I would opt for watchtower over library, a game with a curser or jester, for instance
Watchtower is arguably the most versatile card. It can be almost anything you want it to be, given the right set of circumstances. It's synergies with other cards may be lost on other players, giving you that extra edge.
If watchtower isn't the most underplayed card, it is certainly the most versatile