Robert Hughes, a scientist slowly dying of a plague, wakes up exiled onto a mysterious island that is used for herbalist research. Throughout this island he finds a variety of research outposts from which he finds clues towards the cure he is seeking. Armed with only a compass, wristwatch and notebook, he must find, research and synthesize botanical specimen for the sake of personal survival and navigate the lost island for the overall cure.
The game was released via Steam and GOG on November 28, 2012.
The game uses a simulation of momentum and balance against the characters attributes. The player will find themselves having to resist against momentum as they run uncontrollably down a steep hill or losing their momentum and sliding down some hills if they're low on strength.
Researching a botanical specimen that the player plucks from within the game world can give the player clues as to what plants and fungi can be combined to make a medicine/drug. The player will also discover notes that will reveal recipes.
The player can create items at specific locations by combining two botanical specimens together that will create a drug which will help the player resist and survive the fever that the character suffers from and also items that can permanently or temporarily increase the character's attributes: Strength, Endurance, Perspective.
The player can pick up items off the ground such as rocks, twigs, and other items that can be swung by pressing the mouse button or thrown by holding the mouse button. Some items, like wood, can be used to start fires to provide light when it gets dark.
The player can carry, on their person, one utility item in their right hand and up to three botanical items in their left hand. Within the research outposts there are storage tables where the player can store botanical items. When stored on these tables, that item is available from any other storage table in the game.
The game features a day/night cycle that can be monitored by checking the in-game wrist watch. Nightfall makes exploring even more difficult as you can't see in great distances. To skip time the player can sleep in the beds that are provided within the research outposts.
Within the game, the player has the ability to save the game by sleeping in a bed, which will skip game time forward, or by lighting fires in designated locations such as camp fires, urns, and lanterns.
"The Creature" stalks the player within the open environment between the research outposts. An audio cue of a heartbeat will sound and increase in rate as the creature gets nearer.
To determine the current location on a map, find two established landmarks within view (indicated by a white triangle). With the map selected, select the two land marks and lines will be drawn on the map relative to the locations of the two landmarks. The current location is where those two lines intersect.
Step 1: To determine the position of unknown land marks, first determine the current position (using the above guide) then mark the unknown landmark within that view (indicated by a white triangle with a plus sign). This will draw a reference mark towards the unknown location.
Step 2: To establish that landmark as a "known landmark", travel away from the location in "step 1" getting a different angle on the landmark to be charted. When at a new angle, determine the current position using two established landmarks and then select the same unknown landmark you referenced earlier to establish that landmark. Where the lines of the reference mark and the new angle mark intersect will be the location of that landmark.
The story in Miasmata is told through relics and notes scattered across the island, players can choose to completely ignore the story or invest great amounts of time connecting the dots and uncovering the many mysteries of the island.
Miasmata takes place on an island called Eden, once a research outpost and home to the scientists Dagless, Sanchez, Cornelius and Herbert Gouhs. These researchers were tasked with finding a cure to a sickness referred to as the plague. The plague causes intense fevers, and hallucinations and causes great physical and mental stress, it is also likely that it is highly contagious. The researchers find success in creating two of the three agents in a medicine that is predicted to cure the plague. Around this time, Herbert becomes afflicted with the plague. Although he continues his work for a short time, he eventually succumbs to his hallucinations and descends into madness, murdering all of the researchers on the island. Herbert spends his final days documenting his encounters with a beast which stalks him before mysteriously vanishing.