Strength of will is sorely underrated. 0 cost is nice but you do have to exhaust a character. However, if characters are ready then there probably not going to be in combat so you're not losing an action. Nice, cheap location control.
Strength of Will
Response: After you travel to a location, exhaust a character to place 2 progress tokens on that location.
The Return of the King
Core Set #47. Spirit.
I didn't appreciate this card first, but lately I realized it's actually very good. Cost 0 and the exhaustion of ' character' is good deal for two progress tokens. And the artwork is one of the best in core set. Verdict: 4/5.