Penrod's Heart Spike

Penrod's Heart Spike emerges in The Hero of Ages as a sinister five-inch metal spike covertly embedded in King Penrod's heart, small enough to evade notice while granting an external Allomancer the power to mentally dominate him. This insidious device heals seamlessly into his flesh, enabling subtle manipulation that propels Penrod from a reluctant ruler to a puppet enforcing catastrophic policies amid the world's unraveling. Though confined to the series' climactic third book, the spike exemplifies Hemalurgy's dark precision, underscoring the escalating stakes of cosmic preservation versus destruction.