Competence is an intrinsic need to have a sense of mastery or effectance in any situation. Effectance refers to the experience of affecting change in the world, like a baby delighting at pushing a mobile hanging above it, creating sound and motion.” Effectance is commonly seen as feedback in games. From the UI, to damage/hurt animations, and sound effects, there are many ways in which effectance can be shown in games. Mastery refers to the *experience* of one's growing ability to affect intended change in the world, like a runner experiencing that he can run a mile faster than he was able to before.” Mastery is unlike effectance in that you do not directly provide the aspects that form mastery. Mastery is a personal experience for the player, and as such a designer can only provide the opportunities for the player to showcase and develop mastery. The opportunities commonly provided are based on level design, such as introducing a new jumping mechanic and subsequently laying out the level to showcase that new mechanic. The other most common form is pitting the player against enemies. Enemies provide the player with both the opportunity to use mechanics they are familiar with, while mastering techniques to deal with that type of enemy. 
Consistent factors that affect Competence are feedback and challenge. Challenge is integral because without an action posing a perceived challenge to a user's skill, succeeding in that action doesn't signify mastery, a growth of skills. Feedback is integral because without feedback on the effect of the user's action, (a) there can be no sense of effectance, and (b) without success feedback on a challenging action, there can be no sense of mastery. Even failure feedback is useful, as it potentially informs the user how to act differently. 
Captured above is a scene fromDark Souls. The game provides excellent design elements to support competence. First, notice the HUD (Heads Up Display) in the top left corner. The red bar is a constant meter of health, the green bar a measure of stamina, two values that are integral to playing Dark Souls. They are prominently displayed, allowing player to get constant feedback on the most important elements of the game.
The game also provides, a quick access inventory system in the bottom left, a health bar for the boss, a counter for the amount of souls (currency) the player has collect and finally even a lock on symbol to denote where the focus of the camera will be maintained and attacks will be directed towards. All of these elements serve the purpose of giving the player feedback to understand the current situation that they are in, and how the game is progressing, allows the player to exert mastery by choosing the proper response to feedback, and given that the player succeeds in this situation in game, she will be rewarded with more souls (currency) to power her character, as denoted in the bottom left. Dark Souls provides an excellent example of how to design game components for Competence
As a fighting game, Soul Calibur 5 only thrives if the player can show off their skill with fighters. Therefore, playing people highly above your skill level serves to ruin your attempts to showcase your mastery. Therefore the designers of Soul Calibur 5 implemented a ranked matchmaking system in which players are matched with those of similar skill. Note the bottom left and right for colored squares marked “D5” and “E5” these are the visual representation of the skill level of the player. Therefore when playing a game online, you know that you are being matched against players with similar skill level. Both serving as a visual confirmation of assumed notions and mental stimulant. When playing against lower ranked players, you will go in with more confidence. When beating players of higher rank, you will feel a stronger sense of accomplishment then victories over lesser skilled opponents. This serves two purposes, that all come together to allow the player to develop and maintain Competence.
To make use of this Lens, one must simply think about the balance between empowering the player, keeping the player cognizant of the state of the game, and providing ample challenge to the player.
Player must be given the ability to have effectance within the world. Competence is built from the use of skills and abilities within the context of an action or experience, so the first step is to enable the user to have a chance to do something. The player will never feel competence without being able to see the world change based on their actions. You can give a player the ability to shoot rockets and rocket jump, but if you put them in a small empty room, none of the given abilities will mean anything. Provide the player with worlds that are filled with chances to both use and see the effect of use of the provided skills and abilities. Finally, the player must be able to make personal decision and use the given abilities in open ended situations. The player must personally establish that they can act and act successfully before they will feel competence.
The player must be aware of the game world around them. To design for competence, you must be aware of the important game systems, the information involved in those systems and what the player needs to know to effectively use their abilities and understand the state of the game. Does the player have health or lives? Is there some kind of limit on how much a player can use their powers? Does the player need to be aware of what kind of modifiers their stats are currently using, like armor or rings? For every game there are numerous elements that must be balanced to play effectively, and therefore attain competence.
Each game must be aware of what kind of balance the players feel between their powers and the challenge presented by puzzles, enemies and other obstacles. You have the task of familiarizing the player with your game and subsequent game systems. Always be aware of what you want the player to have to do to maintain a feeling of challenge or difficulty with whatever action they are performing, without erecting an impassable wall of challenge.
The aim of the game designer is to help the player reach a state of flow within the game. One of the common methods of assisting players into their “sweet spot” is by adapting difficulty using dynamic difficulty adjustment, measuring the player's current skill level and presenting appropriate challenge. To thwart competence, the designer must constantly place the level of challenge at the player's ceiling of ability or above. Players will be mentally and physically exhausted when being challenged at their highest level, and feel a lack of effectance in situations where their skill is not sufficient to tackle a challenge. 
The two dimensions in which players have a need to feel mastery are within the interface (controls and graphic interface) of the game, as well as within the rules that govern actions within that environment (e.g. gravity). To properly thwart the player's competence disengage the player from these elements. Create interfaces that lack information, or provide untimely or confusing feedback. Alternatively, make the rules of the game hard to conceptualize or change the rules of the game space consistently. Without even one of the two dimensions the player will have their competence thwarted. 
At the current time, there are no available tools for Competence.
The PENS player experience of need satisfaction competence sub-scale for measuring competence.
The lens is industry standard and empirically validated.
Components: Feedback, Reward, Flow, Difficulty