Fall of Casterly Rock

The Taking of Casterly Rock is an engagement fought during Daenerys Targaryen's invasion of Westeros where the Unsullied, commanded by Grey Worm, conquered Casterly Rock, the seat of House Lannister. After the fall of the castle, they discovered that it was a trap, as the Lannisters only left a skeleton force and had Euron Greyjoy's Iron Fleet burn the invading fleet, trapping the Unsullied into enemy territory