Combo: Rebuild and Tunnel
|Rebuild / Tunnel|
|Set(s)||Dark Ages / Hinterlands|
Rebuild is already a powerful card, turning Estates and Duchies into Provinces without much need for an economy. But Tunnel can turn Rebuild into a Gold generating machine. Just always name Tunnel when using Rebuild - your initial Estates will be turned into Tunnels, and once they are, every time you use Rebuild, you'll be adding three Golds to your deck. You'll also want to outright purchase Tunnels to ensure you get the better part of the Tunnel split, and another couple of Rebuilds as well to set off the Tunnels more often. Once you have enough Gold, just start buying Provinces every turn. The Rebuilds will start hitting those, and very quickly end the game.