From Destinypedia, the Destiny wiki
Gambit is a player vs. player vs. environment game mode in Destiny 2, introduced in the Forsaken expansion. Like the Crucible, weapons and armor can be acquired by completing matches, which can be used in the rest of the game. Likewise, gear received elsewhere in the game can be used in Gambit. The Drifter is the Gambit vendor.
Two teams of four Guardians each are placed into two identical arenas, after a brief break across from each other aboard the Drifter's ship, where the teams can discuss strategy and interact with their opponents. Players compete to kill enemies to collect Motes of Dark, which are deposited at a Bank in the centre of the arena. Up to fifteen Motes can be held at a time, and a player will irretrievably lose all their Motes if they die. Depositing at least five, ten, or fifteen Motes will spawn a Taken enemy, dubbed a Blocker, on the other team's Bank which they must kill to continue depositing Motes. These Blockers are a Ravenous Taken Goblin with at least five Motes, a Ravenous Taken Phalanx with at least ten Motes, and a Major Taken Knight at fifteen Motes.
On occasion, high-value targets will appear, which are minibosses differentiated by a white sparkling aura that drop a large amount of Motes on damage and death, usually enough for a player to nearly fill their Mote inventory. Should a team be trailing greatly behind the opposing team, catch-up targets will appear for them, which are Elite enemies with the same aura as high-value targets that drop more Motes than regular enemies, but not as much as actual high-value targets.
At 25 and 50 Motes deposited, a portal will open up which allows one player to invade the other team's area to hinder their progress by denying Motes. The Invader will have an overshield, be friendly to the opponents' enemies, and be able to see the locations of every opposing player, at the cost of being announced and glowing red for easy visibility to the opposing team. Popular invasion and counter-invasion tactics include the use of Supers, long-range weapons such as sniper rifles, and heavy weapons such as machine guns like Xenophage. Invaders will return to their team once a timer runs out, they eliminate the entire enemy team, or they are killed.
When the bank is full (100 motes), a team will be able to summon a Primeval, a powerful Taken, in their arena, alongside a plethora of Taken minions and two Primeval envoys.  The opposing team's invasion portal will begin to activate periodically. At this point, the goal of the game is to kill the Primeval before the other team is able to kill their own. Killing the Primeval envoys as soon as possible will give the Primeval slayer damage buff to all team members over time. Invasions now serve the purpose of healing the opposing team's Primeval to set back their progress towards winning the round.
The second round of a Gambit match plays identically to the first, with increased enemy difficulty featuring more Elite enemies. If the winning team wins this round, the match ends. Should both teams win only one round, the Sudden Death round is activated, which skips right to the Primeval phase of the match, and all abilities, including Supers, charge significantly quicker.
During Season of the Hunt, Gambit and Gambit Prime were merged into one mode. Matches are now one round, with 100 motes needed to summon Primevals. Blockers are able to drain the opposing team's bank, and banking ten motes summons an Elite Taken Phalanx instead of a Captain. Kell's Grave and Cathedral of Scars were also removed, leaving only 4 maps left.
List of Maps
List of appearances