I just
played a Guilds game with Watno where he played basically Masquerade + Taxman BM, and I trashed down to build a weird engine with just about everything in it. I was definitely behind, but was able to catch up with some interesting plays. The main thing that made this engine work was playing Navigator and then Herold, sometimes chaining 2 or 3 Heralds in a row. this only works if you have both in hand with a Village, but this happened pretty frequently in this trashed deck with Crossroads and Fortress.
I did some other fun things, such as name Fortress with Doctor to get it into my hand, and twice Stonemasoned a Gold to get 2 Duchies late. It was a fun game with some great Guilds combos!