Blackhaven

The Dondarrions' marcher seat, its banner a purple lightning bolt — carried this season by Ser Beric, sent to arrest the Mountain.

The fuller tale

The Dondarrions’ marcher seat, its purple lightning-bolt banner more famous in later generations for Ser Beric’s outlawed brotherhood, backs Storm’s End’s stormlands muster during the Dance without particular incident of its own — one more house whose loyalty follows its liege lord’s into the green camp.

In the first season

Its lord's banner rides out this season: Ned sends Beric Dondarrion to bring the Mountain to justice — an errand that outlives the man who gave it.

The fallen of this place — if any, they are named here. Spoilers.

No death the chronicle records has come to this ground — or none the maesters have set down.