The characters. The single most complex people of the OFF franchise that could be keys to unlocking mysteries. Since there are many different characters, I will start with the most important character and work down.
1. The Batter - The batter is the main protagonist of the story, presumably controlled by the player (or so determined as his conscience), and is the main hero. He, along with his trusty bat and his three add ons, Alpha, Omega and Epsilon, are out to purify the zones of this world.
2. The Queen - Also known as Vader Eloha, is the only other character in the series to have add ons herself, respectively named Delta, Sigma and Upsilon. She is the ruler of all the zones, and knows about each and every happening that occurs in the story. She is the final boss before fighting Hugo, who is later revealed to be the queen's and batter's son. This gives the implication that the queen is the batter's wife, which will be further explained.
3. Hugo- The infant boy who resides in the red room, guarded by the queen. He is also believed to be the son of the batter and the queen. He is known for coughing at every opening speech, as well as fiddling with a little meat stick plushie.
4. The Judge - Who's true name is actually Pablo. The Judge is the one who gives you hints and clues throughout the game. He is also the one who you must fight against or alongside at the end of the game.
5. Elsens - The ever populous citizens of the OFF world. They all look alike, except those at the mines and in the room, and are a very quiet, timid people. Upon exposure to extreme pressure, possessed Elsen explode into smokestacks, becoming dangerous.
6. Dedan - The guardian of Zone 1. He is hostile, cruel, unforgiving, and brutal. He, out of the three, is clearly the most unpleasant to be around.
7. Valerie/Japheth - The guardian of Zone 2. Valerie is originally shown to be the Judge's delusional, feline brother. Once Japheth shows himself, it is revealed that Valerie was no more than a disguise for the vile fire bird.
8. Enoch - The guardian of Zone 3. Enoch is certainly the more reasonable and understanding of the three, but provoking him in the wrong way gets you on his bad side.
9. Specters - The hostile creatures of every zone that either appear, possess, or consume whatever is in their path. This is what the batter sets out to purify and eliminate.
