The Fifteenth Doctor found a Whistle in the Memory TARDIS. (TV: Empire of Death [+]Russell T Davies, Doctor Who series 14 (BBC One and Disney+, 2024).) The Doctor then used the whistle to awaken the Heart of the TARDIS to detach it from Sutekh and kill The Harbinger. (TV: Empire of Death [+]Russell T Davies, Doctor Who series 14 (BBC One and Disney+, 2024).)
Tardis