Dark Knowledge
Revised Core Set #71 (x3)

Attach to a hero. Attached hero gets -1 Willpower

Response: Exhaust Dark Knowledge to look at 1 shadow card that was just dealt to an enemy attacking you.

'Go on then!' said Frodo. 'What do you know?'
'Too much; too many dark things,' said Strider grimly.
–The Fellowship of the Ring