Gaia Project – Auction rules

An auction decides who plays each faction and how many victory points they pay for it. The winning price is deducted from that player’s score at the end of the game. Choosing No auction skips bidding and leaves each player with the faction they selected.

BGS offers four auction modes:

In both sealed modes, everyone can submit at the same time. Bids stay hidden until everyone has submitted, then the game resolves the auction automatically. Submitted bids cannot be changed.

Choose while bidding

The first player chooses a faction at a bid of 0. In turn, a player without a faction can choose a new faction or outbid someone on a faction already chosen. A player holding the winning bid sits out until someone outbids them. Bidding ends when every player holds a faction.

For example, P1 chooses Ivits, P2 bids 2 VP on Ivits, and P1 then chooses Geodens. P2 plays Ivits and loses 2 VP at final scoring; P1 plays Geodens for 0 VP.

Random factions

With Random factions, choices come from a randomly selected pool containing one faction per player. In a three-player game, only those three factions can enter the auction.

Choose factions, then bid

Players first nominate one faction each, in order. A nomination puts a faction into the auction; it does not reserve it for that player.

Players then bid openly in turn. You can claim an unheld faction for 0 VP or outbid its current holder. If you hold a winning bid, you wait until someone outbids you. The auction ends when every faction has a holder.

Random factions

With Random factions, the game selects the factions and goes straight to bidding.

Silent auction (sealed bids)

After the factions have been nominated, enter the most VP you are willing to pay for each faction, including the one you nominated. Use whole numbers from 0 to 40. There is no shared budget: each maximum is independent. Bid higher on factions you want more; bid 0 on one you would only take for free.

Once all submissions are in, the game runs the following auction for you:

1. An unheld faction costs 0. Taking one from another player costs its current price plus 1 VP. Keeping a faction you already hold costs its current price.
2. In seat order, the game compares your maximum minus that cost for every faction. It takes the faction giving you the best result, or leaves you where you are if you already hold a best option.
3. It repeats until everyone keeps their current faction. You pay the resulting price, which can be much lower than your maximum.

For example, your maximums are 6 for Itars and 4 for Taklons. If another player holds Itars at 3, taking it costs 4, leaving a difference of 2. Free Taklons leaves a difference of 4, so the automatic auction prefers Taklons for you.

If several options are equally good, keeping an equally good faction you already hold takes priority. Otherwise, ties favour a faction already held by someone, then the faction you nominated, then the faction nominated latest. These tie-breaks are deterministic, not random.

Preference split (sealed budget split)

After nominations, divide your entire displayed budget between the factions. Use whole numbers; 0 is allowed, and the total must match the budget exactly. The default budget is 20 times the number of players: each player splits 60 points in a three-player game or 80 in a four-player game.

Once everyone has submitted:

1. Add all players’ bids for each faction. Process factions from the highest total to the lowest.
2. Award each faction to its highest bidder who has not already received a faction. Each player gets exactly one.
3. Charge the winner the average of all original bids on that faction, including bids from players who have already won another faction. Round to the nearest whole VP, with halves rounded up.

Your bid expresses a preference, not a maximum price. You can pay more than you bid. For example, four bids of 30, 20, 10 and 0 make a price of 15 VP. If the first two bidders have already won other factions, the player who bid 10 wins this one and pays 15 VP.

Equal faction totals are processed in reverse nomination order: the latest-nominated faction first. Equal eligible bids favour the player who nominated latest. Neither tie-break is random.

Ban phase and turn order

Faction ban phase before choosing is a separate setting. When enabled, each player bans one faction before nominations. A banned faction cannot be chosen in that game.

The first round’s turn order follows the order the factions entered the auction, not the size of the bids or when sealed bids were submitted. Whoever wins the first-nominated faction plays first. Initial booster selection runs in the reverse order.