Back in 2013, I Kickstarted Colossal Cave: The Board Game, a board-game adaptation of Adventure. (See the Kickstarter campaign here. I’m quite proud of that campaign. You can still find copies of the game on Amazon.)

Seven years later, I’ve finally tried out a single-player variant originally inspired by BoardGameGeek poster Tracy Smith, and I’m pleased to say that it works pretty well! In this variant, you’re playing against the clock, trying to deposit as many treasures as you can before the draw pile runs out.

On my first solo playthrough, I scored 6 treasures (out of a possible 15). On my second, I scored 8. On my third, I scored 7. On my fourth, I again scored 8, by using “Empty Bottle” to deposit two treasures on the very last turn of the game. (I also had “Fee Fie Foe Foo!” in my hand, but would have needed two more turns to cash it.)

CC:TBG solo mode

Place only one adventurer pawn on the board. When you take your turn, follow the ordinary rules: draw one, move one, play one. After each of your turns, the “computer player” gets a turn. The computer player has no adventurer pawn, no location, no inventory, and no hand. On the computer’s turn, simply flip one card from the draw pile.

• If it is an action card that can be played right now (such as “Bottomless Pit”), the computer plays it. If the card requires a choice (e.g. “Har Har!” or “Explore at Random” or “Stock Up!”), you may make whatever choice benefits the human player the most. If the card tells you to acquire an item (such as “Stock Up!” or “Fee Fie Foe Foo!”), do all the usual “Acquire” mechanics and then (since the computer has no inventory) place the acquired item straight into the discard pile.

• If it is a reaction card, place it into the computer’s “reaction row.” Cards in the reaction row stay active until they are triggered. Any time the human player does anything, check the cards in the reaction row (from newest to oldest) and trigger the first applicable one, if any. Once a reaction card has been triggered, place it in the discard pile as usual. (Or, if the card wants to go back into your hand, like “Lost in the Maze” and “Stop! Pay Troll!”, place it back in the reaction row instead.)

• If it is a treasure, a non-treasure item, or an action card that isn’t applicable immediately, then simply place it in the discard pile. Such cards are deemed “not playable by the computer.” The computer does nothing this turn.

Keep taking turns — one regular human turn, one flip-a-card computer turn — until someone needs to draw a card and the draw pile is empty. At that point the game ends, and the human player’s score is the total number of treasures they managed to deposit safely in the Well House.

Notes on specific cards

• If the computer player plays “Let’s Do That Again!”, search the discard pile in order from top to bottom for the first card deemed playable by the computer, and then do whatever would have happened if the computer had flipped that card.

• “System Crash” is never deemed playable by the computer. If the human player plays it, nothing happens.

• “Steal a Keeper” is deemed playable only if the human player holds at least one non-treasure item (and its effect is to discard that item). “Your Lamp Is Getting Dim” is deemed playable only if the human player has the Brass Lantern (and its effect is to discard the Brass Lantern). “With What, Your Bare Hands?” is deemed playable only if the human player is in the Hall of the Mountain King. “DROP VASE” is deemed playable only if the human player has the Ming Vase. “Bottomless Pit” is deemed playable only if the human player is currently in darkness.

• “Angry Dwarf” (the action card) is deemed playable unless the human player is in the Well House, regardless of whether the human player is carrying the Little Axe.

• “Wait For Me!” and “Follow Me!” are always deemed playable, but once “Follow Me!” is in the reaction row, it can never be triggered. The human player can still play “Follow Me!” when moving out of a room, but doing so has no particular effect.

• “I Don’t Know How to Do That” is, naturally, triggered the first time the human tries to play any card. (Vice versa, the human player can use it to cancel the effect of a triggered reaction card and send that reaction card straight to the discard pile; or to cancel the effect of an action card flipped by the computer. The human cannot use it to stop the computer from drawing a reaction card into the reaction row.)

• Always deemed playable: “Don Woods Never Existed”, “Explore at Random”, “Fee Fie Foe Foo!”, “You Are Carrying Too Much Already!”, “Stock Up!”

• Never deemed playable: “Pirate Booty”, “Speed Run”, “Xyzzy!”, “Plugh!”, “Plover!”

• “The Cave Is Closing” is always deemed playable. But I tentatively recommend taking it out of the deck no matter how many players you’re playing with.

“The Cave is Closing” is the one card I regret putting in the game. In a multiplayer game, you can’t ignore the possibility that someone will play “The Cave is Closing” and ruin your endgame plan. And simultaneously, it’s fiddly and easy to accidentally screw up — like when someone plays “Har Har!” and then you remember two turns later that they shouldn’t have been able to do that.

Contrariwise, look at the entire “Plover Room” complex — “Plover!”, “Platinum Pyramid,” “Tight Squeeze,” etc. That complex needs improvement, but at least it’s easy to treat those cards as worthless, if you don’t think they’re worth the bother. You can’t choose to ignore “The Cave is Closing” unless you remove it from the deck.

If I were making a second edition, I think I’d replace all instances of “Plover Room” with “Misty Cavern” and change “Tight Squeeze” to acquire the emerald à la “With What, Your Bare Hands?” That might pretty much fix it (although I haven’t playtested the idea).