The Purgatory: Game Concept

Cover image: "Purgatorio, Canto III" by Gustave Doré (1832–1883), from his illustrations for Dante's Divine Comedy. Public domain, via Wikimedia Commons.

This is an old design document I wrote for a game called The Purgatory. It is a soul-collecting platformer about a character trapped between life and death, and the only way out is opening the Gates of Heaven.

I was inspired by games that proved a single, simple, unique mechanic can outshine titles with high-end graphics:

• Continuity
• Closure
• The Company of Myself

Those games pushed me to brainstorm a mechanic of my own that could make a game stand out on its idea alone.

The Purgatory, as the name suggests, is a game about heaven, hell, and souls. You play a stick figure trapped in purgatory. The only way out is to open the holy Gates of Heaven.

There are two basic kinds of souls. Light souls are good and give you more energy. Dark souls drain it. Souls are just blobs of energy drifting in random directions.

Through some unusual circumstance, the character is stuck in purgatory, neither dead nor alive. That state has given him a special power: he can attract and repel energy in the form of souls. The Undead, the Grim Reaper, holds the key to his survival and the way back to the living world.

It is a platform game with these controls:

• WASD / Arrow keys — move around and jump.
• Cmd / Ctrl / Space — attract souls toward yourself (soul magnet).
• Shift — repel souls away from yourself (soul repulsion).
• Left mouse button — fire the soul blaster toward the mouse pointer. Hold to charge: the longer you hold, the more powerful the shot, but it drains your soul energy.

Each level has at least one Heaven Gate and at least one Hell Tunnel, with souls drifting around throughout. You must collect a specific number of white souls to open a Heaven Gate. Hold the attract button to pull souls toward you. Collecting white souls also raises your energy, which fuels your blasts.

• Light Souls (white). The common souls of purgatory. Absorb them for energy, and gather enough to open the Heaven Gates.
• Dark Souls (gray). Avoid these. Destroy them with the soul blaster, or repel them with Shift to push them down a Hell Tunnel. If one latches on and attacks, tap repel quickly to shake it off. Close contact drains your energy.
• Star Souls (yellow). Like the blinking star in Super Mario Bros. that makes you invincible, a star soul lets you convert dark souls into light souls when you blast or attract them, giving you more energy.
• Shield Souls (light pink). Absorbing one wraps you in a temporary shield that blocks dark soul attacks and repels them when you press attract.
• Soul Spark (light soul). A special soul that permanently increases your energy and health and lets you attract and repel faster. The more souls you collect, the sooner a Soul Spark appears.
• Dark Flash (dark soul). Smaller than other dark souls but twice as fast. When you attract souls, it closes in at double speed; when you repel it, it backs off at half speed.
• Winged Angel (light soul). A light soul with wings. Once absorbed, it grants a special power. (Still to be decided.)
• Dark Star (dark soul). The opposite of a star soul: bigger than a normal dark soul and able to fire dark energy beams.

Three dark souls that orbit each other. When they meet a light soul, they circle it and convert it to a dark soul, growing in size and power. They fire small beams of dark energy that you dodge by jumping or repelling. Close contact with the Trio or its attacks drains your energy and releases some of the souls you have absorbed, which the Trio can then absorb to grow stronger. Its attacks include the Tri Blaster (surrounds the player and fires three beams) and the Dark Spiral (spins into a wheel that fires shots along a spiral path).

On one level, scattered dark souls merge into a huge blob of dark energy: the Black Hole. It is very powerful but very slow. Its attacks include the Octopus Missile (eight guided missiles you tackle by repelling) and Black Fission (it splits into smaller blobs that surround the player).

The only soul with a humanoid appearance rather than a blob of energy. The Undead is responsible for carrying souls from the human world to heaven or hell through purgatory, but it has not been doing so lately. Its scythe wields absolute power, and it holds the key to the living world, making it possible to revive the dead. Defeating it is the only way to leave purgatory. Its attacks include Death Absorber (a powerful drain that steals some of your absorbed souls and boosts the Undead's power; evade it by tapping repel rapidly) and Invoking the Dead (summoning the Black Hole or the Grim Trio onto the field).

Making an attack follow a curved path looked like it would be a challenge, but the TweenMax library and its Bezier and BezierThrough plugins made it straightforward:

• Sinusoidal curve
• Parabolic curve
• Spiral curve (this one was a bit tricky)

The idea was to click anywhere on screen and fire a particle from the center toward the mouse, tracing the chosen curve.

Shoot!