OFF

"You have been assigned to a being called "The Batter". The Batter has an important mission. Be sure that it's accomplished."

OFF is an RPG created in 2007 by web user Mortis Ghost. Originally in French, it since got an English translation. The player enters his name and is informed that he is now in control of a being called the Batter, the game's main character, who is a quiet man in a baseball batter's outfit.

Fairly simple, huh? Well, It gets weirder.

The game takes place in a world nothing like what you know. The Batter encounters, only a few moments after you gained control, a white, wise and snarky cat with a Cheshire Cat Grin that calls himself "The Judge". The people in this world, called the Elsens, are practically all Inexplicably Identical Individuals other than the items merchant Zachary, who has perfected Breaking the Fourth Wall (not that the other characters would care for it; the player is repeatedly addressed personally), strange ghosts that terrorize everything in sight and mighty lords of the lands of the world, called zones.

The Batter's mission is to "purify the world" from these specters; And you have to help him with it.

The game's translation can be found here, and the original French version here.

Tropes used in OFF include:

Acrofatic: Enoch, despite being the size of a large hill, is very capable of chasing you down.
Addressing the Player: Both the Batter and the Judge do this.
Advancing Boss of Doom: Enoch.
Animal Stereotype: The Judge is pretty much a walking cat-personality stereotype, albeit more sympathetic.
Batter Up: The Batter uses baseball bats to "purify" specters.
Biblical Motifs: The Add-ons are called "Father", "Son" and "Holy Spirit" in the menu, and the guardians are all named after people from the Bible.
Bonus Boss: Sugar, in zone 0.
Boss Banter: The Queen.
Boss Corridor: Used multiple times.
Breaking the Fourth Wall: Zachary is master of this trope, though the Batter and the Judge do this, too; Could even be considered No Fourth Wall if the Elsens and Guardians broke it, too.
Cheshire Cat Grin: The Judge's face bears a truly majestic example.
Climax Boss
Cowardly Boss: Japhet.
Crap Saccharine World: Quite literally zone 3.
Damage Sponge Boss: All the game's bosses, which is however RPG Maker's fault.
Deadly Euphemism: What "purifying" obviously is; at least in the context of ghosts.
Downer Ending
Everybody's Dead, Dave
Fridge Horror: If you think about it, alone by killing Dedan and making his zone disappear you have doomed the entire world; all elements necessary for the life to go on were won there.
Heel Face Turn: All the guardians as encountered in The Room. Or maybe that's actually how they used to be?
Hopeless Boss Fight: Enoch, in his first form.
I Did What I Had to Do: The Batter.
Inexplicably Identical Individuals: The Elsens, save the ones wearing helmets, becoming Burnt or, later, wearing labcoats.
Jerkass: Dedan. At least in zone 1.
Kick the Dog: Dedan's way with the Elsens. In fact, by Word of God, he was created to be despised.
Killer Space Monkey
Mini Game: The balloon game in zone 2's amusement park and the "Game Of The Mortal Fall" in zone 3.
Moral Event Horizon: The fight against Hugo. Arguably also the one against the Burnt crying for help.
Multiple Endings
My God, What Have I Done?: The player and the Judge.
Nice Job Breaking It, Hero: The Batter. And to a certain extent, the player.
Only a Flesh Wound:

"This... This is not a serious injury... I'm sure..." -Elsen

The Phoenix: Japhet.
Playing the Player
Race Against the Clock: The residential area in zone 2.
Sizeshifter: Enoch. His size ranges from ceiling-height to the size of a building. It is likely an ability of his.
Stout Strength: Enoch, the guardian of zone 3. So much so that he is invincible the first time you face him.
Something Completely Different: The alternate ending. At least it's a pick-me-up after all that happened.
Suspiciously Specific Denial:

"I'm not hiding anything, I promise!" -Elsen

Tragic Villain: Japhet, zone 2's guardian.
Unwitting Pawn: The player and the Judge.
Well-Intentioned Extremist: Enoch.
Would Hurt a Child: The Batter, and the player.