There has been a lot of confusion surrounding the last skill in any guardian's subclass, Illumination. The in game description for Illumination during the Beta was "Seal this subclass, locking previous choices." After Tyson Green (of Bungie) was asked about Illumination in an interview with [url=http://www.eurogamer.net/articles/2014-04-30-how-destiny-turns-into-diablo-when-you-hit-the-level-cap]Eurogamer[/url], Eurogamer release the following information "Destiny allows you to freely swap your ability choices, but according to Green there comes a point when you can lock them in. This gives your guardian benefits, such as a stat boost. At this point you get a copy of the same focus, but that copy levels up much faster, thus allowing experimentation." [b]From this statement we learned two things (both of which have been widely misinterpreted).[/b] [b]1. [/b]At some stage the illumination skill of your subclass becomes available. Using this skill this specific focus is now locked in, giving a stat boost. [b]2. [/b]At this point the character gets a copy of the same focus, but a copy that levels up much faster, thus allowing experimentation. [b]Now lets dive deeper into what these actually mean as well as discuss some of the misconceptions. [/b] To start lets discuss what a focus is. When a player creates a new character (and up until they select the illumination skill) they only have two foci, one for each of the two different subclasses available to that class. A focus can be thought of as a physical item that your character equips (just like their armor or weapons). In the same way that the better weapons and armor have skill trees, a focus has a skill tree that grants the character the powers that are currently selected in that tree. The subclasses of each class are as follows: [b]Hunters[/b] - Gunslinger and Bladedancer [b]Titan[/b] - Striker and Defender [b]Warlock[/b] - Voidwalker and Sunsinger [b]What is the illumination skill? [/b] It is a passive skill in the skill tree of the focus that gives a boost to a character's primary stat(s). Bungie has not said what stat(s) this passive skill will boost or if the player will have a choice. When a player selects the illumination skill the other skills that were active in the skill tree of that focus become locked (meaning they can no longer be changed). This completes that focus and it remains in the characters inventory in one of the three slots for foci. In what was the empty, third slot in the focus portion of the characters inventory will now be a brand new focus of the same subclass of the focus that was completed. This new focus is completely separate of the focus that was completed. It has a band new skill tree that will need to be leveled. One misconception is that this new focus replaces the one that was locked and needs to be re-leveled to unlock the skills that they player locked. This is not true. Note the last part of the statement from Tyson Green that was released by Eurogamer, "At this point you get a copy of the same focus, but that copy levels up much faster, [b]thus allowing experimentation[/b]." The only way to experiment with a new focus is if the skills can be changed; this is how we know for sure that the prior thought is a misconception. Once this new focus has been leveled, players will again be free to activate any skill until they again choose to select the illumination skill. Another misconception is that selecting the illumination skill locks that character into a specific subclass. This is not true. Just as a player can swap the different weapons and armor that are equipped, they can change with focus is equipped. This includes changing between the two different subclasses that are available to a given class. [b]To conclude, there are still some unknowns regarding this mechanic but we have a good guess at the answers: [/b] - Can players store foci in their vault? Our best guess is yes. - Will players be able to use the illumination mechanic on multiple different foci or is it just limited to one focus (once used it is removed as an option for all future foci)? Our best guess is yes. The illuminated skill can be selected (when available) on any number of foci. - How many foci can a character hold in their inventory? We have only ever seen 3 available slots so it will most likely be limited to the 3 at launch.