Duels

Authorized Player vs Player fights, that can take place even in safe areas.

Procedure
To make a duel a player must send a request to another, the second player must accept and may decide then which type of duel it will be.

Types of Duel
The types of duel are:
 * Normal Mode: Rarely used in SAO, since it will only stop when a player's HP reaches 0, and that will mean permanent death for the loser. This is the one used for Sleep PK.
 * First Strike Mode: This is the most common, the winner is decided by whoever lands the first clean hit or whittle the opponent's HP to half.
 * Time-Limit Mode: The winner is determined by whoever has the most HP within the designated time-limit. (unconfirmed)