Mozart was a child prodigy, and as such had gained attention at an early age. He was accustomed to it; thrived off it. He was mostly good natured in his search for attention notwithstanding his knowledge of his own greatness, which could lead him into arrogance at time.
Mozart didn't search for attention simply to make himself happy, he also wanted to make others happy, he wanted to use his music to make them feel exactly what he would conjure on notes fitted together into symphonies. To do that, to manipulate their emotions, he needed their attention fixed upon him.
Most people willingly gave Mozart their attention, whether for his music, his antics, or his bed, they would pay him attention and complement—or on the rare occasion criticism and dislike, still attention was attention, and Mozart knew he was brilliant. He was after all, Wolfgang Amadeus Mozart.
But there was an exception to this rule, and it was the ever reticent Antonio Salieri. Mozart was frustrated beyond belief, after all, they were both composers living in the same town, why should he not enjoy Salieri's friendship? The man was nearly as brilliant as Mozart, and surely beneath all that silence Antonio could not be made of stone.
And so Mozart set about attempting to gain Salieri's attentions, first with subtle methods, inviting the Italian to more of his rehearsals, attempting to follow the societal norms more closely when around the other man, but nothing worked. Mozart began to get desperate, and as the cliché goes 'with desperate times come desperate measures.' Mozart's desperate measure would be gossiped about for years to come. They would begin what some referred to simply as 'The Game'