During the Dance of the Dragons, Black Trombo led a company of Myrish sellswords hired by Lord Hugo Vance. Trombo arranged the ambush of Ser Criston Cole's outriders at Crossed Elms, during which blacks disguised as corpses killed a dozen greens. This led to Cole's dwindling and exhausted army being destroyed at the Butcher's Ball (though it is unclear if Trombo was present at this final assault).
Black Trombo's sellswords from Myr accompanied three hundred Wayfarer's Rest men led by Lord Hugo Vance to the host of Ser Addam Velaryon. Black Trombo claimed that he slew Prince Daeron Targaryen during the Second Battle of Tumbleton by smashing Daeron's face in with a swing of his spiked morningstar. Black Trombo survived the battle, but his fate after that has not been stated: afterwards the river lords' army advanced on King's Landing culminating in the Battle of the Kingsroad, the last battle of the war, but Trombo is not mentioned during these events.