Now we come to the most iconic item in all of computer game history... Adventure's Brass Lantern.
The Brass Lantern provides light. This is extremely valuable, as it defends against the action card "Bottomless Pit" (which makes you Die). Admittedly, bottomless pits are much rarer in CC:TBG than they must have been in the setting of the original Adventure (where just moving between two dark rooms at all would instantly kill you).
In a nod to IF history, particularly the Infocom games, the rules for determining whether an area is lit are fiddlier and more realistic than the rest of the items' behaviors. The Well House and Cobble Crawl are lit no matter what. In every other room, you are in darkness unless there is a Brass Lantern present in the room — regardless of who's carrying it! The Brass Lantern gives light to the whole room. This means that it's a viable tactic to stick close to whoever has the lantern, particularly if they're sitting to your right.
The Brass Lantern is playable in the Well House, of course. It is one of four items found inside the building in the original Adventure (the others being the Iron Keys, the Tasty Food, and the Water Bottle). The action card "Stock Up!" allows you to acquire any one of these four items no matter where you are in the cave, which means it's always possible to get the lamp away from someone even if you don't have "Steal a Keeper".
In fact, there are several more ways to lose the Brass Lantern.
* The action card "Your Lamp is Getting Dim" causes the Brass Lantern to go into the discard pile immediately.
* The Rare Coins (a treasure) can be discarded at the start of the turn to acquire the Lantern, which of course means taking it away from its current owner. This rarely happens, because it's usually such a bad trade: the lamp is great and all, but it's not a treasure.
* "Steal a Keeper" or "Tight Squeeze", as remarked in the previous post.
The reason that the Coins allow you to acquire the Lamp is that in the original Adventure, when your lamp starts getting dim, it is possible to replace the batteries with fresh ones from a vending machine (no kidding!) located in the Maze of Twisty Passages (All Different). All you need to do is put in your coins. Of course, doing this renders the game unwinnable, because you can't get the coins back. The Fresh Batteries did not make the cut into the 72 cards of CC:TBG, although I have a promo card of them (it defends against "Your Lamp is Getting Dim", of course).
Being in the light has one more benefit: if you manage to carry light into the Plover Room, you may play the Platinum Pyramid. In Adventure, the puzzle is how to bring light into the Dark Room (adjacent to the Plover Room); it's only doable by the use of the magic word "Plover". In CC:TBG, one can simply walk into the Plover Room and play the Pyramid, then walk out again, as long as one is sure that the "Tight Squeeze" reaction card isn't in anybody's hand.
Playtesters always forget that the Platinum Pyramid cannot be played in darkness. It says so right on the card (as you'll see when we get up to the Ps), but it's too easy to skim over. I've tweaked the wording a couple of times already, trying to solve this problem. I'll crack it eventually.
Did you know that in Will Crowther's original game, the "shiny brass lamp" was in fact a caver's headlamp? The game's parser recognized "HEADLAMP" as a synonym. It was not until Don Woods started messing with it that the lamp became a "LANTERN" and everyone started associating it with the bulky handheld storm lantern that we know today.