The ten commandments I would always try to follow when making a game:
1. Don't show it, let the player do it.
Sometimes more information can be received from a cut-scene, sometimes text is best, and other times carefully constructed atmosphere can give the most. Different narratives require different amounts of each, but you never want to make the player feel like they are just receiving information and not interacting with the game. This is certain to happen if you show a scene you could have had a player execute. I don't care if all the player could do in a scene is walk over and press a switch, if you don't give back control to the player to do that, they'll be pulled out of the experience. In film there's a rule: "Don't tell, show." This can be view as an extension of that rule for games. You don't want an audience watching a film to wish they could see the event the hero described, and you don't want a player to wish they could do what they see the hero doing on screen.
2. Meaningful actions should have immediate noticeable consequences.
Basic rule to conditioning teaching: the reinforcement has a greater effect the closer it is performed to the behavior it would like to change. A player needs to see or hear right away that what they have done is good or bad, and then later get more detail information telling them how good or bad it is. It's just as important not to send false signals with behavior you don't care about modifying in the player. Games are great teachers when they do this right.
3. Never repeat the same event thrice.
The first time it is brand new. The second time it proves how far along the player has come. After that, it becomes redundant. Some redundancy is unavoidable. An event is a culmination of actions and objectives, and while the actions or objectives may appear again, the event should never repeat. Tetris is the same actions and the same 7 pieces, but the event of placing each block is always changing based on the position of other blocks. Having to perform the same fetch quest multiple times is repeating the event. Three is the limit. You can still have a boss rush at the end of the game, but not two times in a row. Anymore times and the events will begin to feel like filler.
4. Obstacles should be encounter before acquiring the tool to overcome them.
When getting a new tool or key, a player should never think: "What the hell am I going to use this for?" They should be thinking: "Ah ha! With this I can get past the so and so." Knowing what the obstacle is first, allows players to have these little Eureka moments. Also, any reoccurrence of the obstacle seen after gaining the tool will feel linear compared to going back to previously explore areas and opening up the world in a different direction. There's a reason Link doesn't get a tool in a dungeon until he's nearing competition of a dungeon.
5. Give multiple tasks at a time a player can work towards accomplishing.
All games are linear, players only walks the path they are walking, as they do in life. Freedom is not being able to do anything you want, freedom is choice. Players must believe they have a choice to do one thing or another, even if they are merely choosing the order they do things in. It makes the player feel free, it gives them options to avoid feeling stuck on one particular problem, and it can make the game more complex.
6. Game mechanics should reinforce who the characters are.
The things a character can do and the things a player can do as that character, should be the same. Similarly, how a character compares with other characters in certain regards should match who that character is in the narrative being told.
7. Judge a player on what they do, not on what they choose to be.
The biggest issue with moral choice systems is players know when they are choosing to be good or evil. In real life, no man does evil. We do what we feel is best at the moment, and some people may judge us are heroes for our actions while others judge us as villains. A player should never be aware when they are being judged or who is judging them. Giving players option boxes of what to say are too obvious. By basing judgment on a player's actions, you also strength the argument a third party has against them. A player can deny having evil intentions, but cannot deny deeds they perform or didn't perform. Be honest, at this very moment in real life there are thousands of good deeds you failed to do, based on the right point of view. I mean, what have you've done for me lately? And did any of you even think about Zoidberg?
8. Layout future goals and how the current actions lead to achieving it.
The objective of playing games is to determine what it is you're supposed to do. This is unique among any other story structure; someone reading a book usually knows how to continue the story when they reach the end of a page. But all good narratives have a clearly define purpose the audience can follow along. The purpose of the plot may not remain the same, but it's there to define a goal for the protagonist and explain why they are going through the events they are going through. Not all games have narratives, but they all have an ultimate goal and a current task the player is faced with. It is important to let players see how these two are related or there's less motivation in completing the current task.
9. Players should fear losing progress, but the plot should never regress.
How much a player fears death is proportional to how much progress is lost when they die. Controlling this fear is essential in controlling how reckless and cautious a player plays. If you want players to care about their actions in a game, then there must be some level of progress they can lose. However, any narrative a game has should not be undone only to be retold later. Plot points, like exposition, plot twists, and character introductions and deaths, should never be revealed a second time due to lost progress. If a plot point is followed by a boss there must either be: a save point before boss battle, an option to continue and retry boss match, or the boss needs to be easy enough to ensure any player capable of reaching this point in the game may defeat it. The ability to skip any narrative scene will provide a solution to any mistakes player or designer makes that could regress the plot.
10. Always allow a player to pause or stop playing the game.
Games are supposed to be so engaging players cannot put them down. But when you don't allow a player to pause the game during a battle or cutscene, and when you don't give a player an available save point, you're trapping the player to continue playing the game or lose progress. As a player, I should always have the option to stop playing. Maybe there's a mission that needs to be completed between saves, but I should at least be able to pause the game during that mission. People should be able to prioritize their life, and leisure activities should not require participants to devote an unknown continuous amount of their time towards.
