Info on the move Defog

Defog

Move data

Type	flying
Category	Status
Power	0
Accuracy	—
PP	15
Introduced	Generation 4

Defog lowers the target's Evasion by one stage and removes entry hazards and barriers on both sides of the field. The moves affected are: Light Screen, Reflect, Mist, Safeguard, Spikes, Stealth Rock, Sticky Web and Toxic Spikes.

Defog also clears foggy weather in battle (which causes Accuracy loss when present), however this weather condition is only present in Sinnoh (Diamond/Pearl/Platinum) and cannot be created in battle otherwise.

When a Pokémon is holding Flyinium Z and uses its Z-Power, Defog turns into Z-Defog and raises Accuracy one stage, in addition to its usual effect as above.

Defog can be used to clear foggy areas (fog will return upon leaving and re-entering the area). So far only Sinnoh has experienced foggy weather. In Diamond & Pearl, Defog cannot be used outside of battle before obtaining the Fen Badge (Pastoria City Gym); In Platinum it cannot be used before the Relic Badge (Hearthome City Gym).

Game descriptions

Diamond Pearl Platinum	Obstacles are moved, reducing the foe’s evasion stat. It can also be used to clear deep fog, etc.
HeartGold SoulSilver	It reduces the foe’s evasion stat. It also removes spikes, light screens, etc.
Black White Black 2 White 2	A strong wind blows away the target’s obstacles such as Reflect or Light Screen. It also lowers the target’s evasiveness.
X Y O.Ruby A.Sapphire	A strong wind blows away the target’s barriers such as Reflect or Light Screen. This also lowers the target’s evasiveness.
Sun Moon Ultra Sun Ultra Moon	A strong wind blows away the target’s barriers such as Reflect or Light Screen. This also lowers the target’s evasiveness.
Sword Shield	A strong wind blows away the target’s barriers such as Reflect or Light Screen. This also lowers the target’s evasiveness.
B.Diamond S.Pearl	A strong wind blows away the target’s barriers, such as Reflect or Light Screen, and lowers their evasiveness. It’s also one of the Pokétch’s hidden moves.