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Adding subtraction to an addition card game?

4 replies [Last post]
Joined: 09/15/2009

Hey everyone!

For the past few weeks, I have been working on an idea for a card game. The original idea was to make a variant on blackjack/21, but the idea has grown since then.

Currently, the goal of the players is to make "sets" of cards totaling 21 points from 2 different decks of cards: crew and officers. Officer cards are numbered from 1 to 6, and crew cards are numbered from 1 through 10. Each deck has 3 suits.

All of the cards have positive numbers, but I am considering adding negative numbers to some of the crew cards. That way, a player could actually make a set totalling more than 21, but bring the total back down with a negative card. I'd probably keep the negative numbers limited to -1 or -2, to keep things simple.

I remember reading somewhere that subtraction is more difficult to process than addition, and so I am wondering if adding subtraction is a good idea. Do you think that subtraction is harder to do than addition? Would you be put off by a game that included subtraction as part of the mechanics?


Joined: 09/27/2011
Yes and No

I think adding subtraction, in terms of mental calculation, would be fine. I imagine if the numbers are on the scale of 21, they should be able to work it out just fine. More importantly, how would this work thematically? What do you add to a crew to make the people count for less or not at all? Would you add things like cannons, which require a certain number of people to man? Would they be pirates or stowaways? If you have a good thematic idea, then yeah, go for it. If you don't have one, I think you need one for it to make sense and not feel forced.

Joined: 11/10/2009
What's the target audience?

It sounds like a good game so far, but I'm going to make a few assumptions. Please feel free to clarify if I'm off the mark.

From your concern over (mental) subtraction being too difficult for your players, I'm guessing that this is going to be targeted at children. Also, since you talk about adding another card after a >21 sum is reached, I'm going to assume that the players are composing sets from a hand of cards instead of playing cards immediately upon drawing them from a deck.

While subtraction may be harder than addition, I wouldn't necessarily remove it altogether. This sounds like an 'educational' game, where the players might not be learning addition, but they are certainly practicing it. Have the subtraction cards be optional 'advanced level' cards to be added when the children have mastered the basic game. Also, if keeping mental track of sums and differences might be too hard for children, put pips on the cards and have the cards laid down on a table where subtraction cards cover up the appropriate number of pips on the addition cards. As for making them fit in the theme, it's not that hard. Just off the top of my head, I think any of Seasick, Afraid of Heights, Grumpy, Clumsy, Tired, or Confused crewmen would be suitable for a negative modifier.

Another way to accomplish the same goal (changing a 'bust' hand into a winning one) is to have cards that add to the target number, raising 21 to 22 or higher. That eliminates subtraction altogether.

Joined: 09/15/2009
Thanks for the feedback. It

Thanks for the feedback. It sounds like I need to explain the game a bit more, so that we are on the same page.

The theme of the game (currently called "Boarding Party", but that may change) is this: the players are all co-captains on a ship. In the middle of the night, the ship comes upon a derelict treasure galleon. The captains have woken the crew and officers, and ordered them to break into squads and go investigate. Any money found by a squad is brought back to the captain that organized it, so both quantity and quality of the squads is important.

The game consists of 2 decks of cards: Officers and Crew. The Crew deck is approximately 3 times as large as the Officer deck. Both decks of cards have 3 suits: currently Swords, Guns and Bombs.

During a turn, there will be 2 Officer cards laid out on the table, and a pool of 5 Crew cards. Players draw cards from the Crew deck into their hands, and then try to make "squads" of Crew. Each Squad needs an officer to lead them, and those are drawn from the Officer deck. The Squad, including the Officer, must total 21 points. Completed Squads are placed in a player's score pile. If a player is able to make a Squad of only one suit (all Sword cards, for example), they get a bonus of an additional Officer card in their score pile. The game ends when either the Crew or Officer decks run out, and the winner is the player with the most cards (not points) in their score pile. Players subtract cards left in their hands from their total score.

My initial idea was that the value of a card represented a Crew or Officer's effectiveness (in battle, in boarding, etc). Then, some Crew are very ineffective (lazy, drunk, etc), and so have negative value. But, in thinking about this, I'm not sure that fits my theme, because negative value cards will actually add to a player's score pile (if they can use them). Instead, maybe all of the Crew cards have negative values, and players have to balance them against the positive value of the Officer cards (Squads would have to total 0pts to score)? That could simulate an effective Officer motivating a group of unmotivated Crew.


Joined: 02/26/2011
Subtractive Scopa

When I first read the title of this thread, I immediately thought of a game that some freinds from work and I have been playing at lunch quite a bit lately.

There is an old Italian card game called "Scopa", that some friends were talking about a few months ago. I learned the rules, and my lunch group from work has been playing it quite a bit since then. However, the game is very simple, and is based on a simple matching and addition of card values. We have spiced the game up a bit though by adding the ability to either add **or subtract** values.

For many of us, it is a much more fun variant. However, we do occasionally have someone who has difficulty with the variant. Nothing major, just some slight hiccups.

So as this relates to your game, I would say that there is no real problem putting in the subtractive element, but understand that it will cause at least a bit more of a challenge or possible confusion in the game. But of course it could also make the game more interesting, and may therefore be worth it.

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