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(Message started by: Mageant on Mar 3rd, 2013, 3:02pm)

Title: New Game: Nymbat
Post by Mageant on Mar 3rd, 2013, 3:02pm
I have discovered a new abstract game I call Nymbat. It is a race/breakthrough type game.

The idea I had for the game was to make it slightly new (for abstract games), fun (which all games should be) and also difficult for computers to brute-force calculate. I also wanted the rules to be relatively simple but have the dimension of different types of pieces. So instead of defining each piece individually (such as in Chess or Arimaa) the properties of a piece are derived from a number. Thereby I can have a whole range of pieces with only one general rule, using the number as variable.

Nymbat is condensed for "numbers battles". In a way it "simulates" a battlefield which is the intention and inspiration for it.

It has the following rules:

a game by Channing Jones (

Play on a six-sided hexagonal map with 8 hexes per edge (15 hexes width).

Home Row:
Each player has a home row of 8 hexes directly next to an edge that is opposite to the opponent's home row.

Setup Area:
A player's home row and the next two rows to it are his setup area (three rows, 30 hexes).

There is no fixed set of pieces. Instead, each player creates his pieces from a set of possibilities. Each piece in the game has a color to determine to which player it belongs and a whole number from one to six. Other numbers are not allowed. You can use dice, for example. Pieces are placed inside a hex, with only one piece per hex allowed (except during movement).

Reserve Number
Each player notes a reserve number of 60 on a piece of paper or using pieces next to the board.

Both players must agree beforehand who will take the first turn. Players alternate taking turns. On each player's first turn he must bring in reserves with a limit of 30 (see below).

On subsequent turns a player chooses one of the following three options:
  • Bring in Reserves
  • Move a Group
  • Pass

Bring in Reserves:
The player places any number of his pieces on unoccupied hexes in his setup area, but at least one. He may choose the number for each piece (1-6). On his first turn the total of the numbers on the pieces he places may not exceed 30. After his first turn he may place any total if it does not exceed his current reserve number. At the end of his turn he subtracts the total of numbers he placed from his reserve number.

Move a Group:
The player may move any or all of his pieces in one contiguous group (a solitary piece is also considered a group). Each piece may move any number of hexes up to the lowest number in the group. A piece does not have to move in a straight line. He must end the movement of a piece before he can move another. Both the selection of pieces and the distance they can move are determined by the group as it was at the start of the turn. Moving a piece during a turn does not change this. A player's own pieces do not block movement, but they may not end movement together in the same hex. If a player moves a piece into a hex containing an opponent's piece then he must must end its movement there and do removal and breakthrough (see below) before moving the next piece.
Red player can either move group A one hex or group B two hexes.

A player must pass if he has no piece on the board and cannot bring in any new piece. He may also choose to pass.

When a piece ends its move in a hex with an opponent's piece then the opponent's piece is removed from the board. The moving player's piece is also removed if the number on his piece is equal to or lower than the number of the opponent's piece plus the total of opponent pieces' numbers in adjacent hexes. If it is higher then the moving player's piece is not removed. See picture.
Blue player moves and can either remove the red 1 and keep his piece or remove the red 2 and also lose his piece. The two red 3s are supporting the red 2 for a total of 8.

If the removal of an opponent's piece causes a contiguous group of his pieces to be split into two or more groups then all of his pieces adjacent to that piece are also removed from the board (a chain reaction is possible but should only happen in theory). See picture.
Blue player moves, first removes the red 2 and then the red 5, resulting in breakthrough and so the other two red pieces are also removed. Blue also loses both his pieces.

Retreat/Delay Penalty:
A player must reduce his reserve number by one if he retreats on one turn or every seven turns he delays (even if non-consecutive). If his reserve number is zero, then he must instead remove one of his pieces from the board. A turn is considered to be a retreat if a player moves a group effectively further away* from the opponent's home row. A turn is a delay if none of his groups moved effectively closer* to the opponent's home row and he did not bring in any new pieces. A pass is also a delay. If a player removes an opponent's piece on his turn then it is neither a delay nor a retreat in any case. A turn that already is a retreat is also not considered to be a delay in any case.

*) To determine the change of distance to the opponent's home row compare the start with the end of the turn only and by counting the number of hexes from the closest piece of the group each time. Pieces are considered as belonging to the group as it was at the start of the turn only (i.e. splitting up or moving adjacent to other groups does not change group membership for this rule).
Red is retreating since he moved back one row.
Red is delaying. Although one piece has moved backwards, his most forward piece has stayed on the same row, so it stills counts as a delay.

A player wins the game if at the start of his turn he has a piece on his opponent's home row and no opponent's piece is there. If all the pieces on the board have been removed and both players have a reserve of zero, then the player who moved last wins.

You can also download a PDF version of the rules (with pictures) here:

Also there is a module for the Vassal game engine available (for online play):

I would appreciate any feedback/opinions on this.

Title: Re: New Game: Nymbat
Post by Mageant on Mar 3rd, 2013, 3:03pm
Here are some of my thoughts on Nymbat:

I looked more into the possibities of the first move (setup move). There are at least a billion possibilities just for setting up 1s. If you just count the "reasonable" setups using higher numbered pieces then there are at least a million.

The game appears to have the property of nontransitivity ( This would make it an interesting game in my opinion.

At the basis of the game is the dilemma whether to keep your pieces in groups or not.

Advantages of Groups: You want to keep your pieces in large groups so you can move as many pieces on one turn as you can. In groups you also defend better, since adjacent pieces will add their value to force an attacker to lose his piece too.

Disadvantages of Groups: Groups are vulnerable to "Breakthrough". If your opponents manages to split up your group then you will lose a lot of pieces. With a mixed numbered group you will also waste the movement capability of all numbers higher than the lowest number of the group. Basically, the lowest numbered pieces slows down the other pieces. So you want to split up your groups by number for optimal use of movement distance. Also, there is the less obvious disadvantage of having to move more pieces forward if you have large groups. Every three turns you must move forward or else suffer a penalty. So if you are trying to delay then it is a disadvantage to have large groups.

Balance of Pieces
All pieces seem to be balanced in that they all have a use, at least this is my goal. So I hope that "internal balance" as Christian describes it on his website is given.

The higher numbered pieces are obviously the more powerful ones because they can move further and are less likely to be lost when attacking. The disadvantage of course lies in the amount of those pieces you can have (ie. they cost more reserve points). You can have simply more of the lower numbered pieces. You can also win with a lower numbered pieces just as well as with a higher-numbered one.

I've already tested the strategy of taking all 6s or all 5s and then just attacking. The counter-strategy to this is to create lots of 3s and form in triangles (I call it a "shield" formation). The "shield" formation of 3s can be destroyed by 6s or 5s but only at a loss of points (ie. as attacker you lose more reserve points than the defender does). 6s are more vulnerable to this than 5s since the difference is bigger. Against a mass of 5s a few 6s are useful as defender since you can threaten counter-breakthrough.

There are two types of groups (with more than a single piece) which are inherently invulnerable to breakthrough. These are the "shield" formation, groups of three directly adjacent pieces, and "twins" formation of two adjacent pieces. Another group of pieces which can be invulnerable to a breakthrough is a line of pieces with sufficient depth (a "horde"). The depth of the line necessary depends upon the highest numbered group of your opponent. If he only has 2s, then a depth of 3 is sufficient, if he has 3s, then you need a depth of 4 and so on. Less depth is needed depending on the move range of your own pieces if you keep the distance.

Groups of 3s can be defeated with a combination of 1s and 4s.

Note that a twins formation in a defensive situation will beat any single piece, even a 6.

A horde of 1s will gradually push back groups of 2s but will easily be defeated by a large enough number of 5s or 6s.

First Move Advantage
I'm not sure whether there really is a first move advantage in this game or not. It could be that the player who moves first is actually at a disadvantage because then the other player knows what pieces to bring in to counter those.

Title: Re: New Game: Nymbat
Post by christianF on Mar 4th, 2013, 4:16am

on 02/24/13 at 17:47:41, Mageant wrote:
You can also download a PDF version of the rules (with pictures) here:

Also there is a module for the Vassal game engine available (for online play):

I would appreciate any feedback/opinions on this.

Channing sent me Nymbat and I suggested some minor improvements in the phrasing of the rules, as well as the addition of the above diagrams. I think it's an interesting concept. Over the board play indeed suggests the use of dice, that's why I wondered about a square version. Dice fit so nicely on a square board.
This is an excerpt of what I replied:

That being said, the rules are clear. There's some inherent arbitrariness in the concept (values 1-6 and the total reserve of 60) and actual play might eventually finetune those values (well ... not the 1-6 probably). The retreat and delay penalties are well chosen, given their necessity. All in all an interesting concept for a race/breakthrough game. I can't advise you on what to do with it. For me it's art for art's sake and I have no commecial interest, nor a network to support it. You might try Nestor games.

Publication at RGA is also possible, but hardly anyone reads that stuff.

Whatever your plans, I hope you succeed :)

Title: Re: New Game: Nymbat
Post by dunhillmartin on Nov 21st, 2014, 2:48am
Is this a downloadable games? Looks perfect brain twisting games for mobile.

Title: Re: New Game: Nymbat
Post by Mageant on Nov 21st, 2014, 5:20am

on 11/21/14 at 02:48:28, dunhillmartin wrote:
Is this a downloadable games? Looks perfect brain twisting games for mobile.

There is no mobile version yet.

I am working on a website that will have it though ( It's possible that it would also work on a mobile then, too. It will take a few more months though until it is ready.

Title: Re: New Game: Nymbat
Post by mattj256 on Dec 29th, 2014, 7:05pm
It seems like an interesting game but I have no easy way of playing it.
Some minor quibbles:

1. The instructions say the board is 9 hexes per side, but the picture has 8 hexes per side.

2. The way "moving a group" is defined, it's quite hard to play it on a physical board. You'll have to remember what the lowest number was in the group at the start of the turn, even though there may be many movements and/or removals intervening. I was expecting the rule to be that a group must be moved as a unit: you either move the whole group or not at all, and if you move one piece two left then every piece gets moved two left.

3. The description of delay/retreat is unnecessarily complicated. First number all the rows starting from the home row. If any capture takes place, the move is a capture. Otherwise if any piece increases its row number the move is an advance. Otherwise if any piece moves to a different square in the same row, it's a delay. A pass also counts as a delay. Otherwise it's a retreat.

4. In your description of breakthrough, it seems to me that one blue three should be captured and one should remain. I don't see why you would penalize a player for destroying the enemy group. This rule change also makes the rules simpler.

5. I don't understand how a breakthrough could cause a chain reaction. Destroying one contiguous group can't weaken a different contiguous group. I also have a question about the following position:

blue red blue

If blue moves a piece onto the center red piece he will initiate a breakthrough and all three red pieces get captured. Once the blue piece is destroyed, does that initiate a breakthrough against blue? Do all the blue pieces get captured as well?

Thanks for the post. It seems like an interesting game.

Title: Re: New Game: Nymbat
Post by Mageant on Dec 30th, 2014, 9:19am
Hi matt,

I've corrected that now to 8 hexes. There was rule change and this post was not updated properly.

Yes, you have to remember the lowest number in the group. This did not seem to be a problem with any of the playtesters. Moving all pieces of a group in the same fashion seems to be an unnecessary restriction to me.

This is certainly the most unelegant part of the rules. Unfortunately it is necessary otherwise you get repeating "loops" in play. For almost all playtesters this still worked fine after playing the game once or twice. You are welcome to make any suggestions to improve this.

Both blue threes are lost/captured because when you capture an opponent's piece you must not only compare to the piece you are capturing but also add to that all its neighbors. So although the blue three is higher than the red two, the red two get its neighbors (two twos and a five) added to its number for a total of eleven. This works quite well in the game because it gives a player who keeps his pieces together in a group an important defensive advantage.

A breakthrough chain reaction could for example happen if an attacked group were arranged in tree/snowflake-like pattern with three branches. If you take away the center piece then the adjacent piece you keep causing group split ups.

>Once the blue piece is destroyed, does that initiate a >breakthrough against blue? Do all the blue pieces get >captured as well?
No, a player does not suffer breakthrough effect when he loses own pieces during his own turn. Breakthough effects only happen against the non-moving player (whose turn it is *not*).

Title: Re: New Game: Nymbat
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