Each level is procedurally generated by merging of predesigned sections in a random configuration along with random placement of enemies and items. The game's combat is compared to the Souls series, with difficult enemies with certain behaviors the player can learn, and where frequent player-character death is a fundamental part of the game.
At intervals throughout the game, the player must defeat boss enemies known as "Keepers". There are six Keepers in the game—The Concierge, Conjunctivius, The Time Keeper, The Giant, The Hand of the King, and The Collector.
The game includes Twitch integration, allowing viewers, via the stream's chat, to influence the game, such as voting for which upgrade paths the player should take.
Plot
Setting
The plot of Dead Cells is minimalistic, only giving bits of information to the player, as the player character is selectively mute, and lore is fed gradually from area descriptions and background details.
Taking place on an unnamed island, the player character is the Prisoner, a greenish blob of an unknown substance capable of possessing executed bodies in the depths of the island. While the "head" of the Prisoner is immortal, the bodies it possesses are not, and dying will force it to slink back to the Prison Quarters.
Story
The Prisoner awakens in the depths of the Island's prison, next to a giant skeleton with a spear inside of it, a character named "The Giant". A soldier implies that the Prisoner has been trying to escape for an unspecified period of time.
As the Prisoner works their way out of the Prison Quarters, they navigate the Island, and it is revealed that the Island was once a mighty kingdom, until a plague known as "The Malaise" swept through, reducing most of its citizens to mindless zombies or monstrous husks. The Kingdom's Alchemist worked tirelessly to find a cure, but mysteriously disappeared as the King became reclusive. As the kingdom fell, the remaining citizens began to rebel against the King, only to either die by infection, seclusion, or by their own hands.
The Prisoner encounters and fights several entities as they travel across the island: The Concierge, who was once the prison's guard Castaing, before his infection and subsequent transformation into a hulking monster; Conjunctivius, a nameless, faceless bloated corpse that was transformed into a grotesque tentacled Beholder-like monster; and The Time Keeper, a woman with some mastery over time, who continuously resets time each day to prevent her own infection.
They also encounter The Collector, a hooded figure who trades items to the Prisoner in exchange for Cells, which drop from defeated enemies and are implied to be a sort of essence of life; and The Blacksmith and his apprentices, who upgrade the Prisoner's weapons and arsenal.
Eventually, the Prisoner reaches the castle's throne room, and faces off against the Hand of the King, while the King sits seemingly comatose upon his throne. The Prisoner defeats the Hand of the King, takes his weapon, and uses it to kill the King. The King's body violently explodes, destroying the Prisoner's host body and resetting the game, though giving the Prisoner the ability to act outside of a host body while still possessing the body.
As the Prisoner's head returns to the quarters to find a new corpse to possess, it remarks on how even though the king has died, nothing has changed.
Rise of the Giant
The Rise of the Giant downloadable content adds additional content, including new endings. The Prisoner gains access to a new area of the Island, The Cavern, which houses the titanic undead skeletal Giant, who acts as the boss for the area. Upon defeat, The Giant reveals that the Prisoner is actually the King himself, his soul split from his body by consequence of his and the Alchemist's experiments.
As the Prisoner continues, The Time Keeper begins actively altering the timeline to prevent her own death. After defeating the Hand of the King again, if the player has all five Boss Cells (modifiers which make the game substantially more difficult, earned by beating the game on each difficulty) active, they are able to gain access to the Astrolab and the Observatory.
There, the Prisoner can find the Collector, who is implied to be the King's Alchemist. The Collector reveals that he has been collecting cells to create a Panacea, to cure the Malaise once and for all. The Collector however, upon drinking the Panacea, goes mad with power and attempts to kill the Prisoner to reset the game so they will bring him more cells.
While fighting the Collector, the Prisoner drinks some of the Panacea, which, upon the Collector's death, causes the Prisoner's host body to evaporate, resetting the game once more.
This time however, the Time Keeper fully resets the timeline. This allows the Prisoner, upon reaching the throne room and defeating the Hand of the King, to possess the King, getting his original body back.
However, the body is infected with the Malaise, and so to prevent his own decay, he continues to the Observatory to face the Collector again. This time, upon the Collector's defeat, the Panacea cures the King and binds his body and soul once more.
The King returns to his throne, where he remarks over a glass of wine that he was honestly having more fun crawling around the sewers, when, due to the Time Keeper's meddling, a time-displaced Prisoner arrives in the throne room. The King and the Prisoner face off, and begin to duel.
