Based on the Marvel Comics universe, Marvel: Avengers Alliance is a superhero role-playing game where the player assumes the role of an agent of S.H.I.E.L.D., the preeminent espionage and law enforcement agency in the world. The player must recruit and train a team of superheroes from various Marvel properties, which they then take into combat against a host of villains in 3-on-3, turn-based battles. The agent character is a required character in all battles, with the player able to customize their name and appearance to personal taste, as well as armor and equipment to affect which techniques and effects are used in combat. Additional characters are either earned through progress (Iron Man is the starter team member) or by purchasing them on the recruit screen with Character Points. Characters are drawn from teams and titles such as the Avengers, the X-Men, and the Fantastic Four. As standard for the RPG genre, characters earn XP in combat and level up, earning new abilities/techniques as they progress. Items can be purchased in the shop, and players can research new technologies to improve the equipment available to them.
The story is paramount in Avengers Alliance, with the game being divided up into seasons, chapters, and missions. Each season, chapter, and mission is accompanied by a brief exchange of dialogue between characters outlining the main conflict, revealing details about the story, or adding a bit of character flavor to battles with comments, boasts, and taunts by hero and villain alike.
Missions consist of a number of battles played on the same city board, in locations such as various New York neighborhoods (like Chinatown or Roosevelt Island) or cities like San Francisco. Each mission features a particular villain, with the player first playing a number of easier battles against their henchmen or sidekicks, with the board finally culminating with a boss battle against the featured antagonist. Battles are ranked as easy, medium, or hard, with each being worth a certain amount of progress toward unlocking more battles. Each battle is scored based on how much damage the player inflicted on the opponent and how much damage they incurred in exchange. The player can also send some of their team of heroes on deploy missions, where a hero is sent away for a brief time, usually one or two battles. No other action is required on the player’s part to succeed, and deploy missions offer item rewards.
Once the main villain is defeated, the mission is considered completed, and the player receives a total score based on all their actions. Certain score milestones correlate to stars that are awarded; each star filled yields a reward, with the maximum being five stars. Missions can be replayed as many times as the player wishes, with scores being cumulative toward the star awards. Five missions (plus an optional Premium mission) make up a chapter, with each mission contributing a bit to the larger story and earlier missions often leading up to the final mission in a chapter; the final mission might even feature the same villain as an earlier mission, only more difficult.
Twelve total missions make up an entire season. Each season consists of a long story-arc, with a theme and plot threads that have been spread throughout each mission and chapter.
Occasionally the game will offer a special operation, or spec op, which is only available for a limited time and offers an exclusive character upon completion. Spec ops are one chapter long with six missions. In addition to defeating the missions, the player must complete additional tasks (obtaining items, researching new equipment, earning five stars) in order to fully complete the spec op and earn the limited edition characters. Spec ops are often tie-ins intended to promote other Marvel products, such as the Avengers film or the Avengers vs. X-Men event in the comics.
In addition to the story elements, Avengers Alliance also has a player-vs-player element. The player can face off against another player’s team in a three-on-three battle, with the same mechanics as the story battles. Battles are not played live; the player is matched up with a random player in the database, with that team’s actions being determined by a bot. The player’s team will also be available for other players to challenge when the player is not available, with the player being notified of the results when they next load the game. Players are awarded or deducted points based on their battle record, with all players being ranked. PvP is played in seasons, and at the conclusion players receive various awards based on their ranks. Even low ranks can earn in-game currency (silver).
Marvel: Avengers Alliance features in-app purchases of gold, which can be used to purchase character and items, complete tasks, or speed up research.