Looney Labs Icehouse Mailing list Archive

[Icehouse] New 3House/Treehouse game: Stacktics

  • From"Adam B. Norberg" <abn1@xxxxxxxxxxxxx>
  • DateMon, 25 Dec 2006 10:29:02 -0600
Merry Christmas, y'all! I've been silent on this list for way too long, and
it's high time I do something about it. I've invented a new Icehouse game
for 2 players, and it can be played with a 3house set and a Volcano board-
actually, that's the best way to play it. But an introductory form of the
game can be played with a single Treehouse set and a quarter of a
chessboard, and players up for a more complex, longer game can use an entire
stash per player- or more, with a larger board and some creativity in
starting layouts.

I've playtested this game several times with my father, so this is the
fourth revision of the rules. The game was inspired by Stack Chess- an
interesting game, but with moderately complicated rules and aspects of play
I found uninteresting. Stacktics is streamlined, simpler, and has some very
fascinating emergent strategies that aren't quite as chaotic as Stack Chess.
Credit to Northern Berkshire Game Group for the original Stack Chess, and
serious credit to Kory Heath for his extensive discussions of elegance in
game design, and his design history of Zendo- his lessons about elegance for
its own sake encouraged me to close my eyes and throw out the fiddliest
rules I had, and come out with a much better game in the process.

Notes about which rules are the most likely to be altered are in [brackets].
Unfortunately, this exercise has made it clear to me that I am poor at
writing out rules; the game is *much* simpler than these rules would imply.
Rewriting help would be desperately appreciated, as would webspace for the
final version.


A 3House game for 2 players

Goal: To capture half of your opponents' force (by pip count) before xe can
do the same to you.

Pieces: For the regular version of the game, each player needs three
Icehouse trees of the same color. (Players with only two Treehouse sets can
improvise by assigning two colors per player and considering those colors to
be identical throughout the game.) This "size 3" game is played on a Volcano
board (or some other 5x5 board; pieces remain upright throughout the game,
so space to lie down is not required).

The introductory version requires two Icehouse trees per color for each
player. (One Treehouse set can be used by, again, assigning two colors per
player.) This is played on a 4x4 board (quarter chessboard).

A more complex version of the game can be played with four or five stashes
per player; these are best played on a 6x6 and 7x6 board, respectively. (A
7x7 board can be used for the "size-5" game, but it may be more prone to
stalled games in which players can indefinitely evade capture. This variant
has never been playtested.) [Board sizes for large games are very much still
up in the air. For that matter, 2x2 on a 3x5 board needs to be

Setup: Place the board between the two players. For the size-5 game, the
board should be set up wide; the 7-square edges should be closest to the
players. Assemble each players' pieces into trees, then place them upright
(as trees) in the rows of the board closest to the players, leaving the
corner squares empty. (The piece armies will be on opposite sides of the
board.) Choose a player to make the first move by any random method.

Play: On the size-2 game (played on a 4x4 board), the pie rule is required
to balance the start of the game. (The small armies and the small board make
the first move a massive advantage without this balance.) The first player
moves one of the pieces; the second player may then take the opposite set of
pieces and make a response move, or switch sides (claiming the stash moved
by the first player) and the "first" player now makes the response move with
the second army (and will, of course, be referred to as the second player
for the remainder of the rules.) [The 4x4 game is too small to not give a
massive winning advantage to the first player. There is a fairly obvious
opening move that gives the first player control from the start and it
requires a blunder by the first player to ever lose it. All pure strategy
games are either solvable or drawn, and 4x4 Stacktics is small enough for it
to be solved slightly too easily. The pie rule forbids the first player from
taking this unstoppable advantage. The problem is much less severe in a
larger game; the board size is less relevant than having three of each size
of piece rather than two. However, the pie rule may need to be implemented
for larger games if it turns out to be simpler than playtesting has

All subsequent turns (and all turns in larger games) simply alternate,
players alternating single moves as described below. Captured pieces should
be counted after every capture; if one player has captured more than 3 *
gamesize pips worth of xir opponent's pieces, that player has won the game.
[This needs to be reworded. I'm trying to express that a size-2 game needs 6
points to win, a standard size-3 game needs 9, a size-4 needs 12, and a
size-5 needs 15. Astute readers will note that this is half of the army, by
pip count, but it's easier to immediately count by describing this as 3 *

Movement: Pieces can move individually or in stacks, although stacks have a
limited move range. Every move has a "base piece". If a single piece is
being moved, it is the base; otherwise, the bottom of the stack is the base.
A move does not have to use a piece on the ground as its base; a stack may
be split in the middle, or a piece peeled off the top, by using the middle
or top of the stack as the base.

The shape of the move is specified by the size of the base piece, while the
maximum distance of the move is specified by how heavy the stack on top of
the base piece is ("weight" is the sum of the pip counts of the pieces on
top). Pieces above the base do not affect the shape of the move. Small
Icehouse pieces move along diagonals, like bishops in Chess. Medium pieces
move along straight lines (like rooks), and large pieces can move as either
(like queens).

The maximum distance of a move depends on whether a piece is moving alone,
moving loaded, or moving overloaded. If a single piece (instead of a stack)
is being moved, the piece is moving alone and there is no maximum distance
on its move. (A piece may never move over other pieces along its movement
path, although it may under some circumstances land on top of other pieces,
forming a stack if that piece is friendly and making a capture if it is
not.) A stack in which the sum of the pip-counts of the pieces on top of the
base is less than the pip-count of the base is moving loaded. On a size 2 or
size 3 game, it can move at most 2 squares; a size 4 or 5 game allows it a
move of 3 squares. A stack with an equal or greater pip-count of carried
pieces compared to the single base piece is considered overloaded, and it
may move only a single square. ["Overloaded" is probably a bad term. Despite
the restricted move, "overloaded" stacks are often some of the most
important strategic arrangements in the game, mostly because matched pairs
of pieces moving together are surprisingly powerful. The overload rule is
triggered on "equal weight" *because* pair stacks need to be restricted in
this way, or else they are far too effective.]

Pieces may stack if the base of the move is the same size or smaller than
the top piece of the friendly stack in the square that would be the target
of the move. If the stack is legal, place the moved piece or pieces on top
of the piece or pieces already in the square; do not reorganize them. If the
top piece is smaller, the move is illegal and the square cannot be entered
by the active stack. (Remember, you can't jump over pieces already on the

Captures can only be performed by a SINGLE piece moving off the top of a
stack. A pair of pieces moving off a stack of three cannot capture and
therefore cannot enter a square occupied by opposing pieces under any
circumstances. A single piece flat on the ground (not part of a stack) also
cannot capture. The only legal attacking piece is a piece starting its move
on top of a stack containing at least two pieces, counting itself. Captures
are done by occupation; move this piece to a square occupied by opposing
pieces to capture the entire stack on that square. (The attacking piece
stays in the square.) Size is irrelevant; a small can capture a stack of
three large pieces the same way a large piece can capture a single small.
[The legal stack restrictions are therefore not in force.] Captured pieces
are removed from the board and cannot be re-entered. [Remember, the count of
captured piece pips decides the end of the game- I need to mention this
here, but I don't know how to do it coherently. These rules are already
several times as long as they need to be. For that matter, the
single-piece-capture is sort of unclear.]

Game End: If at any time a player has captured half or more of his
opponents' force by pip count, that player has won the game.

Clarifications: Move shape is decided only by the bottom piece of whatever
stack (or single piece) is being moved; the maximum distance of a move is
determined by how many pieces are above it. A small (which can only have
smalls stacked on top of it by the stacking rules) that is not moving alone
is always Overloaded. A full tree is very versatile: the entire tree can
move one space in any direction, the top two pieces can be moved as a stack
up to two spaces as a rook, or the small on top can be moved any distance as
a bishop, and may capture. 

Maximum move distances are not the only permitted move distances; a Loaded
stack may move one space instead of two, and a single piece can stop at any
distance. Passing is prohibited; pieces may not choose to move zero spaces.

Pairs of identical pieces stacked on each other are among the most important
strategic configurations in the game. (The first capture is devastating in a
size-2 game because it prevents at least one size of stack from being
created. If the first capture is a Queen, the player losing the queen has
probably lost the game unless an immediate forced counterattack has been
planned. Losing a large in a size-2 game is worse than losing both a small
and a medium; protect a single queen in preference to a 1-2 stack.) This is
the *only* configuration in which attacks can advance along the board. The
piece on top can move freely and attack, and then the second piece in the
stack can make an identical move and re-form the stack any distance away in
two moves- possibly after the first move was a capture. This is in contrast
to all other positions, in which the attacking piece is smaller than the
piece it rests on; it would be an illegal stack for the second piece to try
to move on top of the first, even if the move shapes would allow for it in
the first place.

This game is much deeper than it might seem at first. Chess skill is very
beneficial to quickly understanding the strategy of the game. All your
pieces are important as they are flexible in different ways; large pieces
are valuable and offer the widest variety of moves, but small pieces can go
on top of any other piece and are therefore the most common piece to make
attacks. Queens can only attack in pairs, and a two-queen stack is
Overloaded and is relatively unmanuverable- but because attacks have
unlimited range (they are single pieces; single pieces are never loaded)
they control very large portions of the board.

Endgame terms, board sizes, and starting positions are the most mutable
parts of these rules. Board sizes are semi-arbitrary for the large games and
there may be better ways of doing them. Restricting diagonal moves by making
a size-2 game play on a 3x5 board instead of a 4x4 board may greatly even up
the opening game; on a board this size, position the board so the short
edges are to the players and start with trees in the corners. The pie rule
may not be necessary for this board, but more playtesting is required to
determine this; at the very least, it plays very differently from a 4x4.

The size-2 game is nowhere near as interesting as the size-3 game because
the first unmatched capture often confers a devastating advantage. The size
3 game may be the best version for normal people, but chess fans are likely
to prefer the longer games of size-4 or size-5 boards. Endgames on larger
boards play quite differently, because single stacks control smaller
proportions of the board.

Part of my design goal for this game was to invent a game that plays best
with a 3House set (help Andy sell 'em!), but can be played in some form with
just a single stash of Treehouse pieces to give people an idea for the
game... and make them want to buy at least one more set to play the better
version of the game.

Sorry about how badly written these rules are. I write like a computer
scientist: I specify everything in unambiguous detail and in the process
create something completely illegible to anybody without a law degree. These
rules *should* by all rights be one page long; I can explain the entire game
to someone in under ten minutes. Help with a rewrite, with playtesting, and
with fixing the size-2 game (and improving other versions!) would be greatly
appreciated, and I'd love to hear what those of y'all more experienced at
inventing games have to say about this one! I think it's the best of the
games I've invented so far, no matter what the game system; this is the
first one that I'm truly happy with instead of "okay, well, it's sort of
interesting but I can't think of how to do better, let's just play something
else" like I am for my other designs.

I'd like all the feedback I can get. Thanks for y'all's attention, and I
hope you enjoy the game!

--Adam B. Norberg

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