Auctions

Owns a lot (item, quantity, optional reserve price), the standing bids, and a clock. Bidders submit or raise bids under a format: ascending open outcry, sealed bid, descending price, or a timed listing with a buyout price. When the clock ends or no bidder will go higher, the rule assigns the lot to the winner, transfers money, and settles fees. AI bidders bid up to a valuation computed from their needs and cash. M.U.L.E. (1983) runs real-time auctions for each resource, breaks ties in favor of the trailing player, and lets players who withhold supply raise prices on later turns; its designers replaced land auctions with one free plot per turn because auctioning land fed a runaway loop. MMO auction houses such as World of Warcraft's use timed listings with a minimum bid and an optional buyout price.

Reading rivals. The player estimates what a lot is worth to each competitor, decides how far to push the price, and feels the sting of overpaying or the relief of a bargain. In real-time formats such as M.U.L.E. bidding is a test of nerve and timing; in timed listings it becomes patient sniping and undercutting.

• auction format (ascending, sealed-bid first or second price, descending, timed listing with buyout)
• tie-breaking and catch-up rules, such as awarding ties to the trailing player
• reserve prices, minimum increments, and listing fees or deposits that act as money sinks
• auction duration and whether bidding happens in real time or between turns
• AI bidder valuation function and how much cash it holds back
• which goods are auctioned versus sold at fixed prices or granted for free

• Auctioning productive assets such as land lets the richest player buy more production, the snowball M.U.L.E.'s designers removed by granting free plots.
• AI bidders with simple valuation rules can be baited into overpaying or never compete, so auctions become trivial.
• Long timed auctions in MMOs reward bots and last-second sniping over judgment.
• Collusion between human bidders suppresses prices when the rules cannot detect it.

• Withholding supply from an auction raises clearing prices on later rounds, enabling deliberate shortage play.
• Bidding wars between two rivals let a third party buy cheaply elsewhere.
• Reserve prices and fees act as money sinks that slow inflation in persistent economies.

• Can LLM bidders with private valuations and bluffing make single-player auctions as tense as multiplayer ones?
• Which catch-up rules (tie-breaks, budget caps) prevent auction snowballs without feeling arbitrary?