never thought much of this card, till i had a run in with nightmare locations. escape from dol-guldur has some of the nastiest locations in the game (torture chamber and dungeon labyrinth). These locations, even alone, could spell creeping doom. Together, they're terrifying (as well as other cards in the deck that add resources to them). Approaching this quest I tried to incorporate as many location control cards as I could. Thorin's Key, strider's path, and shortcut are all great in that quest, but I consider this attachment the single best card for that quest, simply because it allowed you to keep switching these nasty locations out before they ended the game. It's a weird thematic image though, using a compass to navigate a dungeon : )
Attach to a or a Scout character.
Response: At the beginning of the travel phase, exhaust Mariner's Compass and attached character to search the top 5 cards of the encounter deck for a location. Switch that location with a location in the staging area. Shuffle the encounter deck.
The Grey Havens #8. Leadership.
This card is very underrated. For only one resource (in , a sphere with many extra resources lying around) you get the ability to customize your staging area. This allows you to swap out locations that give off nasty effects while in the staging area, and swapping for a more manageable location. Of course, since its only the top 5 cards of the encounter deck, you will have a limited selection of locations to choose from (probably 2 on average). However, you will only be swapping out the worst locations in play, so even worst case scenario, you will swap the location with another that's equally terrible. But a lot of the time, you will swap it out for something better, such as lower . This card is especially useful in , because there are so few location control cards in , increasing this cards value.
This card works well on any combat focused character because it allows the character to perform a useful action if no enemy is going to engage you. Some prime targets for this card are Lindon Navigator because she can quest and then navigate with the compass, Forlong in a Outlands deck (because of his built in readying effect), Rider of Rohan, Rammas Lookout, Ceorl (and is in sphere), Haldan, Idraen, Lanwyn, Angbor the Fearless, Knight of Dale, Orthanc Guard, Wandering Exile (for the same reasons as the navigator), Halbarad, and especially North Realm Lookout (because it activates his ability and synergizes with Dale decks). It works the best with characters such as those, but it can really work well with any or Scout character.
And that's the beauty of the card, its really flexible and provides a useful effect at a cheap cost (and that's without considering that this card lets you instantly obtain your guarded cards such as The Arkenstone by swapping out the location). This card isn't going to hold your team together but it does provide some useful location management for decks that need it.