I analyse Shelley’s fraught relationship with Byron’s self-monumentalising, flippantly self-mocking poetics and personal pride, arguing that Shelley’s notion of a ‘Promethean’ poet who catches the strains of general human ‘sympathy’ tenses productively against what he saw as Byron’s narrow drive to create an elevated poetic ‘self’. Shelley, though he admired Byron’s poetics in many ways, also saw his friend as being at risk, poetically and personally, of the sort of inflexible remove that the Promethean poet might fall into if their overreaching ambition comes to render them ‘cold’ and removed from their historical moment. Though acts of intertextual intimacy with Byron’s work, Shelley explores various forms of ‘coldness’: some Byronic laments for the trials of human mutability, some distinctively Shelleyan forms of ‘coldness’ that strive to regenerate, through defamiliarisation, the very ‘ashes and sparks’ of creativity that the poet, with their largely unavoidable removal from the world, risks disdaining.