The player's ability is also an aspect that influences game progression a lot. We can talk on it as the effectiveness level the player has when executing certain mechanics. This means skill, precision, coordination, dexterity, resistance, etc. Abilities are developed. First, there is an ignorance state in which the player doesn't know what to do. Then we get to a training phase in which the player learns the mechanics' functioning. This then turns into a training on these mechanics. The more we practice them, the more we optimize the execution process as both the brain and the hands usually answer in a faster and more efficient way. Don't forget about what we said in the first module when we were talking on patterns and their utility. While designing a level we must know how to demand the player the appropriate ability. To do so we must adapt to the target's characteristics. If we demand a lot we create motivating challenges, but if we go too far we cause impotence and frustration feelings. Ability can also be shown in a graphics format, drawing how it evolves through the game. During all levels the player must be constantly learning. We basically force him to learn his avatar's mechanics as well as the other scenario elements', including enemies. Also we give them information on the challenges, objectives and story. All this information needs to be properly distributed, progressively as if it is condensed in few moments the player collapses. It is better to give concrete and non-extensive information pills and then leave some playable time so that the player can assimilate this information and even practice it to consolidate his training. In example, in many games, when you get a new weapon for the first time you can use it without restrictions for a while so that you can train. Let's not forget that learning new things is one of the aspects that generate more interest and fun and so it is convenient to do it during the whole game. The learning graph is also used to show how the player's learning level evolves during the game time. When talking on learning we must talk on tutorials, which are usually levels or parts of them made so that the player can learn mechanics. Usually they are at the beginning of video games, although usually there are mini-tutorials in some middle-point of the game. Often, the tutorial is made by putting information in written format inside the interface, which favors that the player can access this information whenever he needs it. Finally it is necessary to say that progression can be treated in a particular way in preeminently multiplayer games, as in them the difficulty depends a lot on the other player's ability level. In this case, progression works mostly by balancing the groups and rivals assignation to make abilities more or less similar, and the players with less experience can learn without frustrations. In these games it is also very frequent the regular addition of new contents to keep interest and fun in already expert players.