The game is driven through a deck of cards, and at the beginning this deck contains 12 Expansion cards from "A" to "L" (representing the expansion chips) plus 9 Building cards which represent the initial buildings which can be found in the town. During a round of play, each player will have a hand of four of these cards, with three of the cards coming from his right neighbor (from the previous turn) and one additional card drawn from the deck. All players simultaneously chose one of these cards, and then they will reveal their cards on perform an action with it. When all actions have been performed, the round is over, the remaining cards are passed on and this process starts anew.

A player may opt to play any of these cards either with or without a Building tile from his own stockpile. If the card is played without a Building tile, the player will receive a benefit depending on the nature of the card. If it's an Expansion card with a letter, the player will receive a Building tile or a resource (his choice), but if it is a Building card, the benefit received will be determined by the colour and height of the building. So, yellow buildings provide victory points, blue buildings new Building tiles and red buildings resources, and the number of items which may be taken depends on the height of the building depicted on the card. At the beginning of the game all buildings have a height of only one level, but this will increase during the course of the game, thus making the action more efficient.

As indicated, the chosen card also may be accompanied by a Building tile coming from the player's stocks, and in this case the Building tile will be placed upon the property (expansion chip OR existing building) depicted on the card. Thus, the town will either expand its size (expansion), or one of the buildings will grow in height (heightening). Depending on the height of the newly placed Building tile, the player needs to place resources from his stockpile onto the newly placed building, e.g. if the new tile increases a building to a height of three levels three resources must be placed on the building. If the player does not have enough resources, the building may not be placed.

If a new Building tile from the player's stocks is brought into play, the player takes the corresponding Building card from the card stocks and places it close at hand. At the next exhaustion of the deck, this Building card (and other new cards) will be shuffled into the deck, so that the new Building card now can be used by the players for new actions.

Both actions which are accompanied by a Building tile (expansion or heightening) once again provide the player with a bonus, but whereas expansion grants the player victory points, new Building tiles and resources, heightening means that the Building card of the now overbuild building may be kept by the player who has performed the action. Like the Character cards, the Building card will give its owner a new special ability, and this either means that an in-game action gets more effective or that the player has a possibility to score additional victory points at the end of the game.

In fact, apart from owning enough resources the placement of new Building tiles often depends on the number of the building, since it is easier to overbuild a building with a lower number with a building with a higher number. It is possible to build in the opposite order, but this forces the player who does so to lose some victory points. Even Building tiles placed by other players may be overbuilt, and in this case the player who had placed the now overbuilt tile will get back his resources plus an amount of victory points depending on the height of the building. As can be seen, the numbers of the Building tiles are really important for a player to decide on his actions, since high numbered tiles may be quite useful in the endgame to replace some other tiles. However, the tiles with high numbers also have the best benefits on their Building cards, and so players may be tempted to play such a Building tile early in order to bring its card into play.

Trying to explain the rules of Ginkgopolis within a review is no easy task, but despite this observation the game offers a rather well constructed gameflow, and it is rather multi-facetted even though the players can only chose between three types of actions. Quite ingenious is the interrelation between the placement of a Building tile and the adding of its Building card to the deck, because a player who places a new building cannot be certain that he will later be able to collect this Building card. The other players will long to collect high-ranking cards as well, and since a card can only be collected through the "heightening" action this means that the player who has initially brought the card into play by placement of the Building tile then will be displaced by the placement of yet another tile.

In fact, tactical displacement of other players is crucial to win the game, because victory points will not only be collected by fulfilling the conditions listed on Building cards owned by the players, but when the game is over there will also be an evaluation of the city itself. The players will be awarded additional points if they are able to dominate a city district (having most resources in an area of two or more Building tiles of the same colour), and so they will often use the heightening action in order to split and create city districts or to change the current majority situation in a district.

Taken together, all these elements give the game an astonishing playing depth, but this does not come at the usual price of the game getting overburdened with intricate rules. While it is true that one or two games are needed to get to grips with the general mechanism, the game continues in a charming and light-footed atmosphere which is quite rare for this tactical level. The whole playing experience is augmented even further by a rather nice graphical design (including individual drawings for many Character cards), and to my mind all this makes Ginkgopolis one of the most underrated games of the gaming year 2012.