Maestro
Maestro was the child of the Toymaker, and, where their father embodied a game, they embodied the "essence of music". Maestro fed on music, and was fanatically opposed to anyone other than themself playing it, wanting to absorb all music in the universe — with their sights set on the music of the spheres — until they were the only being left.
Biography
After the Fourteenth Doctor cast salt at the edge of the universe, where "the walls" were "thin", (TV: Wild Blue Yonder [+]Loading...["Wild Blue Yonder (TV story)"]) the Toymaker was able to get into the mainland universe. After the Fourteenth and Fifteenth Doctors defeated him, (TV: The Giggle [+]Loading...["The Giggle (TV story)"]) he warned them that his "legions" were coming, a warning soon fulfilled when Maestro was summoned into reality by composer Timothy Drake. Drake had rediscovered the Lost Chord, a musical chord incorporating the Devil's Chord. After emerging in 1920s England, their arrival foreshadowed by that of Henry Arbinger, Maestro sucked out all the music within Drake's heart, then continued with the rest of humanity, all the way to a 1962 where music was all but extinct.
It was then that the Fifteenth Doctor and Ruby Sunday arrived, being baffled to discover a world without music in which the Beatles were recording uninspired drivel and intending to go out of the music business entirely after just one album. Wanting to test the limits of the phenomenon, Ruby played a song she'd composed for her friend Trudy on a piano on the rooftop of Abby Road Studios. Maestro was duly summoned, identifying themself to the Doctor as a member of the Pantheon by laughing through the Giggle arpeggio.
Maestro gave The Doctor and Ruby chase with their tuning fork, threatening them with musical notes until the Doctor used his Sonic screwdriver to create a wave of silence. Maestro disrupted this silence with their fork and a puddle, but the Doctor and Ruby had already escaped.
Finding the Doctor and Ruby once more in the ruins of music-less 2024 London, Maestro threatened the Doctor, and revealed themself to be The Toymaker's child, whining about how their "daddy" was so mean. Maestro attacked the TARDIS with the Harold Saxon drumbeat, and the Doctor and Ruby barely escaped, returning to 1962.
Capturing Ruby, Maestro was baffled when the Carol of the Bells turned out to be buried within her heart with a power which Maestro recognised as that of the Oldest One. Thrown off their game, Maestro was challenged to a music battle by the two time-travellers, ending with the Doctor almost figuring out the Lost Chord. Things briefly looked grim as the Doctor got the final note wrong. However, while Maestro was toying with their two victims, trapping the Doctor in a drum and Ruby in a double bass, John Lennon wandered by the piano and completed the sequence based on his own musical "genius", forcibly sucking Maestro back into the piano from which they'd emerged when first revealing themself, and forcing them out of the universe altogether. Before being fully banished, Maestro snarled at the Doctor that the coming of the One Who Waits was imminent. (TV: The Devil's Chord [+]Loading...["The Devil's Chord (TV story)"])
