Ambush at Dragonstone

  "Rook's Rest had left Aegon bent and twisted, his once handsome face puffy from milk of the poppy, with burn scars covering half his body. Rhaenyra, ever defiant, told her dear brother that she'd hoped he was dead. "After you!", Aegon answered."

- Joffrey Baratheon The Ambush in Dragonstone was the conclusive showdown in the power struggle between Aegon II and Rhaenyra I known as the Dance of the Dragons. The confrontation prepared by Aegon to put an end to the life of his sister secured his apparent triumph in maintaining the throne for hiself, but it did not mean the end of the struggle between the factions enmityed in the war nor prevented his own death  months later in the hands of his own loyalist.

It is only mentioned in  Histories & Lore.