This is the main game package for Commander Keen: Invasion of the Vorticons, a classic DOS platformer originally released on December 18, 1990. Players step into the role of Billy Blaze, an eight-year-old who becomes Commander Keen, the defender of Earth. The collection features three distinct episodes: "Marooned on Mars," "The Earth Explodes," and "Keen Must Die!" Each episode presents players with alien environments to explore, puzzles to solve, and extraterrestrial adversaries to overcome.

The gameplay is built on a consistent EGA scrolling platform engine across all three adventures. Players navigate levels from a 2D side-scrolling perspective, controlling Commander Keen's movement, including running and jumping. A key mechanic is the use of Keen's signature pogo stick, which is essential for reaching higher platforms and traversing gaps, and can also be used offensively. Combat is handled with a ray gun, and progression often involves finding keys, activating switches, and solving environmental puzzles within intricate maze-like levels.

What is the premise of this game?

The narrative follows Commander Keen on his missions to protect Earth from alien threats. His adventures take him to various planets where he must thwart the plans of the Vorticons and their allies. The story is conveyed through the game's environments and level progression, detailing Keen's efforts to safeguard the planet.

What are the core gameplay mechanics?

The gameplay centers on 2D side-scrolling platforming. Players control Commander Keen, who can run, jump, and utilize a pogo stick for enhanced mobility and combat. A ray gun serves as Keen's primary weapon for dealing with enemies. Level design incorporates environmental puzzles that require players to find items, interact with switches, and navigate complex layouts to advance.

What makes this game unique?

The game's distinctiveness stems from its charming child protagonist and its combination of challenging platforming with puzzle-solving elements. The pogo stick serves as a versatile tool for both traversal and offense, adding a unique layer to the gameplay mechanics. The episodic structure allows for varied settings and enemy types across the three included adventures, contributing to a diverse experience.

What are the included episodes?

This main game package features three distinct episodes:

Marooned on Mars
The Earth Explodes
Keen Must Die!

What platforms is this game available on?

Commander Keen: Invasion of the Vorticons is a classic title originally developed for and playable on DOS.

When was this game released?

The original release date for this collection was December 18, 1990.