What are the pros and cons to elective mode in Diablo 3? The smack you in the face pro is you put any skill available into any slot on your hotkey bar instead of being forced into 1 of each category. But what other advantages and disadvantages are there?
The disadvantage of elective mode is that it makes it much easier for you to make some really poor skill choices.
Another disadvantage of elective mode is that it allows you to accidentally drag skills off your action bar. EDIT: Please note that as of patch 1.0.4, skills can only be dragged off the action bar when the skill menu is open, preventing this from being an issue moving forward.
The idea of the "non-elective" layout is to help guide new players into taking balanced builds, that incorporate a good mix of primary offense, secondary offense, defense, and utility.
For example, in elective mode, a wizard could choose to use no signature spells. This means that once they run out of arcane energy, they'd have to resort to melee. While melee builds for wizards are viable, ones that involve swinging a weapon with no arcane skills boosting damage are going to be less than optimal.
The advantage of elective mode is that it gives experienced players much more flexibility in their skill builds, and gives the freedom to try some unusual, but potentially viable, builds.
As James has pointed out, it also allows you greater control over the binding of keys/buttons to skills, letting you use setups that may feel more natural or easier to use than those imposed by the non-elective version.
What is Elective Mode?
By default, Elective Mode is an option in the game that is turned off. It's recommended to turn this on when you get a chance.
Elective mode allows the player to place multiple skills from the same category to their key bindings.
How do I turn Elective Mode on?
Once you join a game, simply hit ESC > Options > Gameplay > toggle on Elective Mode.
What does Elective Mode allow you to do?
By default, the attack buttons in Diablo 3 are bound to the following: Left mouse button, right mouse button, and the 1, 2, 3, and 4 keys on the keyboard.
The skills in Diablo 3 fall into six categories. These categories vary by class, but every class has six. E.g., The Wizard's six categories are: Primary, Secondary, Defensive, Force, Conjuration, and Mastery.
With elective mode off, a wizards Primary skill must be bound to the left mouse button, a Secondary skill must be bound to the right mouse button, a Defensive skill skill must be bound to the 1 key, a force skill must be bound to the 2 key, a Conjuration skill must be bound to the 3 key, and a Mastery skill must be bound to the 4 key.
By extension, it means the player can only use one skill from each category when selecting which six skills to use. Once they choose a Primary skill, that is the only Primary skill they can use until they switch it out with another Primary skill.
With Elective Mode on, the player is allowed to place multiple skills from the same category on their key bindings. A player could use four Primary skills if they so desired.
With a basic Ice Wizard build with Elective Mode turned on, the player can select both two Defensive and two Force skills. With Elective Mode off, this would not be possible since the player would be forbidden from using multiple skills from the same category.
tl;dr: Leaving Elective Mode off will limit your skill choice combinations, and by extension, customization. It is highly recommended that you turn it on as soon as possible.