Change your preferences here.
If the wielder is the target of an attack, all of the attacker's Attack, Special Attack, and accuracy stat stages are ignored during damage calculation and accuracy checks. If the wielder is attacking, all of the defender's Defense, Special Defense, and evasion stat stages are ignored during damage calculation and accuracy checks. If the wielder uses Punishment or the opposing Pokemon uses Stored Power, stat boosts still factor into its power. If the wielder hits itself in its confusion, its altered Attack and Defense stats are kept during damage calculation.
There is only one viable user of Unaware currently, and that is Quagsire. Quagsire, however, is a very good Pokemon this generation and a solid Pokemon to use on a stall team. Unaware can be a fantastic ability in that sense as it will prevent Pokemon that would otherwise destroy stall teams from setting up to do so, who are walled or countered by Quagsire due to its bulkiness and great typing. So it has some competitive use, but it is more or less limited to only one Pokemon at this time.
Found in Dream World