Mask of Truth- Find and destroy the first 30 golden spiders. It will allow you to talk to animals and gossip stones.
Zora Mask- Push the beached Zora over to land, then talk to him and play the Song of Healing for him. It will allow you to transform into Zora Link.
Kamaro's Mask- Play the Song of healing for the guy doing the snake dance on the mushroom structures by Clock Town.
Gibdo's Mask- Play Song of Healing for the mummy in the closet of the musical house.
Garo's Mask- Defeat the milk-selling guy in a horse race by riding into his ranch on Milk Road with Epona.
Captain's Hat- Defeat the big skeleton in the graveyard and open the chest on the roof. Will let you communicate with skeletons.
Giant's Mask- Find it in the room before the boss of dungeon 4. Use it to fight the bosses (Twin Mold).
Fierce Deity's Mask- Complete all the mini dungeons before the final battle. You will need all 20 of the other regular masks (not including the Deku Nuts Mask, Goron Mask, and Zora Mask). This mask will turn you into adult Link to combat the final bosses.
Breman Mask - Talk to the old man with the music box in Clock Town at night. He is found by the stream.
Bunny Hood- Round up the chicks on day 3 in the shed in the back of the Romani Ranch using the Buruu Face.
Don Gero's Mask- Give the meat found in the Goron Village to the Goron with the frog on it's head. It will let you talk to frogs.
Mask of Scents- Chase the Deku Prime Minister through the mini mase on the side of the Deku Nuts Kingdom after rescuing the Deku princess. Will allow you to find mushrooms.
Goron Mask- Use the Lens of Truth outside the cave where you got it and follow the ghostly Goron. Climb up the wall when you get to it using the Lens still, then talk to him in the cave and play the Song of Healing. It will allow you to transform into Goron Link.
Romani's Mask- Complete the poe sidequests on the Romani Ranch on day 1 and 2. It can be used to get into the Milk Bar.
Circus Leader's Mask- Play the songs under the light in the Milk Bar for the man who is shaped like an egg.
Kafei's Mask- Given to you by the fat lady in one of the buildings on the east side of town.
Night Mask- Stop the burgler at 0:00 on day 1, then buy it for 500 rupees on day 3 from the Mani shop.
Blast Mask- Stop the burgler at 0:00 on day 1 by slashing him with your sword. You can blow yourself up with it.
Stone Mask- Use the Lens of Truth by the Ikana graveyad and give some medicine to the injured soldier you see.
Big Fiary Mask - Return the lone fairy found in Clock Town at night to the spring in Clock Town. This will cause faries in dungeons to fly towards Link.
Deku Mask- You automatically get it when you return to the mask collector on day 1 for the second time. Changes Link into Deku Link, one of the 3 transformation masks.
Postman's Hat- Beat Anju and Kafei's side quest
couples mask - Beat Anju and Kafei's side quest