The next non-Hobbit character to make a successful influence attempt (e.g., against a faction, an opponent's character, etc.) must immediately make a corruption check modified by -4. Discard this card after this corruption check.
Plus this can be used to protect your own characters, factions, allies, and even items from being influenced by your opponent - a wizard's the only character that has a reasonable chance of doing it, and they're not going to want to risk a -4 corruption check on him (pretty huge, the only characters who cancel all or most of that are Hobbits and it doesn't affect them). They might also try someone else with a huge influence boost, say from The One Ring, which gives you +5 to it, but in that case there's probably corruption (6 with The One Ring) to contend with instead. It might make them waste a faction on a weaker, less important character (remember, it says SUCCESSFUL incfluence attempt) and just make them blow a faction (hopefully a good one like in my next review).
There are, however, a few problems with using this card. The first is if your opponent is trying to destroy The One Ring instead (although unless they have Gollum to destroy it without Cracks of Doom, they've got to contend with a -4 corruption check that way, too) in which case this card is useless. The second is if they just use a character with no items or corruption cards to get rid of it, either a carefully saved Wizard or a weak (doesn't deserve items) character to influence some low-influence faction. Overall, though, this is a great card, one of the best Hazards in the game, and probably THE best Lure or corruption card.
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