Half-Life 2's Invisible Tutorial

The problem is that two different systems collide (in the example of Terraria). Having an open world game and a learning curve for the things the user needs to understand to progress. Looking up informations in a wiki most often happens when the game gets boring or overly complex for the player to have fun (check Mihaly Csikszentmihalyi's flow theory on that). Games that do that well, such as Zelda (which does this very well) introduce new mechanics and scenarios in an very iterative way. By having a linear structure. Other games use AI to control the gameplay flow. A linear level structure could look like this: A & B are different types of enemies | A (new enemy) | A,A (more complex situation) | B (new enemy) | B,B (more complex situation) | A,B (new combination) | A,A,B,B (complex new combination) | ... This method works with lots of systems, such as level design elements, enemies or construction of ingame elements. The problem is that procedural content generation and open worlds make it hard for the game designer to introduce the content to the player in this order. interesting videos on this topic: - ▶ this video (Half-Life 2's Invisible Tutorial) - link (Director AI for Balancing In-Game Experiences) - link (Can we Improve Tutorials for Complex Games?)