Well, I figured you didn't build anything and probably just recruited pikemen near the village. I built pikemen and spent money on them that I should have spent more wisely.
Added 2 minutes ago
Okay, it's time to reveal my strategy. :)
I don't remember if I bought troops in enemy Castles, I don't think so (they were all bought out). Oh, I remember, I bought trolls. In my own Castles, I bought peasants once to capture the sand mine.
And in terms of building, I only built the Castle, the Shipyard, a ship, and the Magic Tower. That's it.
Added 2 minutes ago
You got it! :)
You suggested it, so you reveal it, and I'll support you...