Only target of the card is a minion character. According to general rules it is restricted to player's character.Treason the Greatest Foe wrote:Playable during the site phase on a minion if a non-Wizard hero is at the same site and the hero and minion have the same home site. Make a roll (draw a #). If the result plus target minion's unused direct influence is greater than the hero's mind plus his player's unused general influence, discard the hero (and all cards he controls) and place this card in your marshalling point pile. Otherwise, discard this card.
"non-Wizard hero is at the same site" is condition but not target. According to general rules such entity may be an opponent's character.
Thanks to its text the card may be used to discard an opponent's character (for FW player, also its own character).
There is one problem. There may be more than one eligible hero character at resolution of the card (at declaration too).
Specifying the hero character at declaration means targeting it. Such approach would break much of a sense of the card, restricting it to be usable only by FW player.
Proposed clarification:
"If there is more than one eligible hero character at resolution of the card, you must choose one of them. The result of roll will be compared against the chosen character's mind (plus his controlling player's unused general influence) and only the character (along with all cards he controls) may be discarded in result of the roll."
EDIT: Changed thread's title to reflect its status. It is no longer proposed clarification, but proposed errata.