Interaction & exchange
The core act is a transaction or contest between players over shared or transferable things: trading, bidding, drafting, voting.
30 entries. Tie-break question: Is it a transaction between players?
Alliances
Players agree among themselves, outside any rules enforcement, to coordinate future actions against other players, with the understanding that the agreement can be broken whenever breaking it pays.
Auction and Bidding
Players compete for an item, right, or position by offering bids under a stated auction procedure, with the item going to the highest or otherwise winning bid and the price set by the players rather than by the rules.
Audience Participation
A rule gives people who are not players, such as spectators, viewers, or a studio audience, a defined input into a game in progress, by vote, suggestion, or shared control, so the crowd affects the outcome without holding a seat.
Ball Possession
One side at a time holds the right to advance and score with a single contested object, and that right transfers by turnover, by scoring, or by a rule such as a boundary or a violation, so play alternates between attack and defence.
Commodity Currency
The standard medium of exchange between players is a consumable item with its own use in play, so every trade weighs use value against exchange value and every use removes money from circulation
Contract Bidding
Before play, players compete to declare how much they will achieve, such as a number of tricks, the highest declaration becomes a binding contract, and scoring rewards fulfilling it and penalises falling short.
Cooperate or Defect
Players each secretly choose to cooperate or defect over a shared payoff and reveal together, so mutual cooperation divides it, a lone defector takes it, and mutual defection usually forfeits it.
Cooperative Play
All players share a single win condition against the game system itself, so they win or lose together and the only opponent is an automated threat that escalates unless the group coordinates its actions.
Deal-Making
Players strike specific bargains whose terms include future conduct, such as an attack withheld, a vote cast, or a later payment, and the rules decide whether those terms bind or rest on trust.
Divide and Choose
One player splits a shared pool into one portion per player, the others choose portions in turn, and the divider takes the portion left over, so the divider is pushed to make portions they value equally.
Drafting
Players select items in turn from a shared pool or from packs passed around the table, so that each pick both builds a private holding and removes the item from everyone else's options.
Ghost Data
A recorded run, usually the best one so far, is replayed alongside a live attempt on the same course as a non-interfering figure, so the player races or compares against a past performance rather than a live opponent.
Gifting
A player sends an item or resource to another player who owes nothing in return under the rules, so the transfer is one-way and any reciprocity rests on custom rather than on agreed terms.
Group Finder
An automated queue assembles players, usually strangers, into a temporary cooperative group for a chosen piece of content by filling required role slots such as tank, healer and damage, then places the group in it together
High-Score Tables
A machine or service keeps a ranked list of the best final scores achieved on a game, usually with a short name or initials entered by each scorer, and shows it to later players as targets to beat.
Loot Distribution
A cooperating group allocates each shared reward, such as a boss drop or a treasure hoard, among its members by a stated rule, such as ranked need and greed rolls, turns, a leader's award, banked points or per-player loot
One Versus Many
One player runs the opposition against all the other players, who cooperate to defeat them; the two sides play by different rules, the solo player is a competitor rather than a facilitator, and their position is not secretly logged.
Player Elimination
A player who meets a loss condition is removed from play while the game continues for the others, so the session ends only when one player remains or a separate end condition fires.
Player Invasions
A player enters another player's ongoing single-player session as a hostile, uninvited or on a trigger the host has set, and the intrusion ends when one of them is defeated or the host clears the area
Rating and Matchmaking
A numerical rating moves after each game by transferring points from loser to winner in proportion to how unexpected the result was, and a pairing rule uses the ratings to decide who plays whom next.
Security Zones
A shared world is divided into areas with graded rules on attacking other players, from areas where any attack is a crime to areas with no rules, and an attack the area forbids flags the attacker for retribution by the system or by players
Semi-Cooperative
Players compete for an individual win but share a loss condition driven by the game, so if the common threat prevails every player loses and each must weigh feeding the shared defence against advancing alone.
Shared Holdings
A group pools assets in storage it holds in common, behind access rights set by rank or role, and any member with access can withdraw them, within any limit the rules set
Side Conversion
A player who is caught or defeated joins the side that caught them for the rest of the round, so that one side grows as the other shrinks until every player is on one side or a time limit ends the round
Take That
A player spends a card or ability to inflict a direct setback on a chosen opponent, such as a lost turn, discarded resources, or damage, which the target can rarely prevent and which costs the attacker little.
Team Play
Players are grouped by rule into fixed teams that win or lose together, with scores pooled and often with differentiated roles inside the team, so the contest is between groups rather than individuals.
Tournament Formats
A fixed schedule and pairing rule composes many individual games into one larger contest, such as a knockout bracket, a round robin, or a Swiss system, and decides who advances, who is eliminated, and how the field is placed.
Trading
Players exchange resources, cards, or other holdings directly with one another at terms they negotiate themselves, so that the rate of exchange is set by the players rather than fixed by the rules.
Trick-Taking
Players each contribute one card from hand to a round called a trick under a follow-suit rule, the highest card by rank or trump wins the trick, and the number or content of tricks won is scored.
Voting
A decision binding on the whole table is made by counting players' declared preferences under a stated rule such as majority, plurality, or unanimity, so persuasion before the count is the real contest.