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Space Quest II is the tenth Sierra title to utilize the Adventure Game Interpreter (AGI) engine used in other Sierra games (e.g. King's Quest I and Leisure Suit Larry I). Apart from walking, your every action, from looking at something to escaping a demented alien hunter with a taste for human flesh is taken care of by typing in an appropriate command on the keyboard. According to Space Quest II Manual, AGI understands the following commands:

CALL	CLIMB	DIVE	DRINK
EAT	EXAMINE	GET	HIDE
HIT	PICK UP	PLAY	KICK
HOLD	LOOK	OPEN	PLAY
PRESS	PUT	RUB	SEARCH
TAKE	THROW	TIE	USE

In order to communicate commands with ease, this guide will highlight the each command in italicized font, like this: take keycard. For the summary of commands needed to complete 'Space Quest II, please see Appendix B.

Since Space Quest II (like many other Sierra On-Line Adventures) utilizes a point system, the walkthrough will provide every action necessary for scoring the maximal amount of points. The point value per action will appear in square brackets immediately following the description of your action, like this: [0]

Although included appendices contain some curious material regarding the gems of the Space Quest II experience, the full enjoyment of the game comes from the slow paced exploration. In other words, use look around as much as possible, and if you can, ditch this guide. Oftentimes (as shown in Appendix A) knowing the solution can diminish the experience, stripping it of the whimsical complexity of the game's design.

Last but not least, it should be mentioned that some find Sierra adventures to be exceptionally frustrating because of high risk of death. Since this game was made before "Try Again" feature was implemented, your only choices are Restore, Restart, and Quit. While the guide does not explicitly tells you to save your game, it is imperative that you save your progress often. Even the most die-hard fans of the series will admit that beating any of the Space Quest games without saving at least once is not an easy trial to endure (although not impossible).