Conquest

When all 3 of your Strongholds are on a single card, you may buy that card after your normal turn action by paying its usual cost, taking your Strongholds back. This happens before the token limit check and before checking for a Noble or a City, and tokens or cards gained this turn can pay for it, so you can buy twice, take tokens then buy, or reserve then buy. It counts as a purchase, so you place, move or remove a Stronghold again, then replace both bought cards.