You gain another superiority die at 7th level.
Additional Superiority Die
Raw data
{
"name": "Additional Superiority Die",
"page": 73,
"level": 7,
"__prop": "subclassFeature",
"header": 2,
"source": "PHB",
"entries": [
"You gain another superiority die at 7th level."
],
"className": "Fighter",
"classSource": "PHB",
"subclassSource": "PHB",
"subclassShortName": "Battle Master"
}