These are the formidable talons of a Harpy Eagle, one of the largest species of raptor on Earth. Let them serve as a reminder that bloodthirsty dinosaurs live among us, that they are descended from downy forebears, and that, yes, feathered animals can be downright terrifying.
https://gizmodo.com/all-the-proof-you-need-that-bloodthirsty-dinosaurs-live-5982218
For reference:
Also for reference:
See also: The feet of a cassowary.
[reddit via Wil Wheaton]