Currently, the game restarts every time a page is refreshed. We can keep progress by saving the completed level locally. Furthermore, we can store the current level that is in progress so a player resumes at the exact point they left the game. We are going to discuss local storage in Project 5, Building an Isometric City Game, when creating the isometric city-building game.

A level-unlocking game usually works better with stars collection. In each quest level, we can define three levels of achievement. Each achievement rewards the player with one star. For example, completion of a quest can be worth the first star, no-undo is worth the second star, and the final star is awarded only when a player completes the level very fast.

Then, we may have a total count of all the collected stars, and it can be used to unlock new quests or even unlocking new abilities to help player advances.