Angel (Auld Mortality's universe)
From Tardis Wiki, the free Doctor Who reference
The "angels", or "storm of angels", were sentient crystals that appeared in 1588. They communicated to Doctor John Dee whilst inside his ship, asking what he'd like to wish for. The Doctor found out that it was his fiddling with the Possibility Generator and history itself that made the beings appear. (AUDIO: A Storm of Angels)