Here are all of the masks in Majora's Mask in alphebetical order!
All Night Mask-Get this mask by saving the old lady from the thief on the first night in North Clock Town at around 12 AM in the night. Then on the 3rd night, buy this mask from the Curiosity Shop. This mask enables you to stay awake for grandma's two stories at the Stock Pot Inn, which can get you 2 heart pieces if you say "I dunno" for her question after both of the stories.
Blast Mask-To get this mask, save the old lady from the thief in North Clock Town on the first Night by slicing the robber. Then talk to the lady to get the mask. It enables you to blow the mask up on command. Do not use when you have low health for it takes some of your health too.
Bremen Mask-Get this mask by going to the Laundry pool on the first or second night and listen to the organ grinder man tell his story. This mask enables you to round up chickens at the chicken coop in Romani's Ranch, which gets you the bunny hood.
Bunny Hood-To get this mask, go to the chicken coop at Romani Ranch late in the final day. Talk to the man sitting and then use the Bremen Mask to round up 10 chicks, which will turn into full grown Cucco's if you keep parading with them. Then he will give you the Bunny Hood, which enables you to run faster and jump further.
Captains Mask-To get this mask, you have to go through the process of killing the Skull Keena at the Graveyard. (To do this, go up to where Dampe's house is, and walk up to the skull of the Skull Keena and play the Song of Storms. Then follow him up the slope[bunny hood reccommended], defeating the Stal Children heeding your way. Stay on his heels all the way and then attack him. Defeat him to get the mask.) This mask enables you to talk to Stal Children, which helps you get an empty bottle.
Circus Leader Mask-To get this mask, go to the Milk Bar on the night of day 1 or 2 with the Romani's Mask on and play music for the manager of the Indigo Go's there on stage with all four of your forms.(Link, Zora Link, Deku Scrub Link, and Goron Link). When your done, talk to the now crying Gorman brother to get the mask. This mask helps you a lot when saving the milk cans from the other Gorman Brothers on the Milk Run with Cremia. If you put it on before getting in the wagon on the milk run, they won't attack you.
Couple's Mask-This mask is obtained through the very long and confusing Anju and Kafei Quest. It is used to quell the argument in the Mayor's Office, which gets you a heart piece.
Deku Mask-You start off the game with this, or actually as this. It is vital in the Woodfall temple and you can fly from flowers, hop across water 5 times, and spit bubbles(consumes magic).
Don Gero's Mask-To obtain this mask, light all of the torches up with fire in the Goron Home in the village. Then go to the little ramp leading into the chandelier. Starting back near where the baby's chamber is, put on the Goron Mask and do a charge up roll quickly off of it, hitting the chandelier. A peice of Goron Sirloin will fall. Take it to the freezing Goron Mailman at Mountain Village and throw it up to him. He will give you the Don Gero's Mask as gratitude. This mask enables you to round up the five frogs for a heart piece.
Fierce Diety's Mask-Perhaps one of the most coveted masks, it is gotten by getting all twenty masks and talking to the children on the moon and finding them in their little games of hide and seek. Then if you talk to the child wearing Majora's Mask after giving all 20 masks away, he wil give you this mask. It makes Link taller and stronger, but his defense drops a bit. Seriously, I doubted this mask, but here's an idea of how powerful it is. It made the final 3 bosses of Majora's Mask seem like a warm up act! All you have to do it use your sword, nothing else. You can beat Odolwa of the Woodfall Temple with 4 quick, consecutive jabs with this mask. It's worth getting!
Garo's Mask-To get this mask, race the Gorman Brothers at Gorman Ranch with Empona. I found the easiest way to win is to pace your self sort of and to occasionally shoot their horses with arrows(kind of fun too!) Though if you don't have good accuracy, just race without shooting. It can be just as easy if you use your carrots wisely.(never use the last one) This mask enables you to find shadow ninja's and is useful in beating the dungeon in Ikana Castle, as after you beat the Garo's it summons, they give you helpful tips..
Giant's Mask-Gotten by
defeating the Eyegore in the room before the bosses chamber in Stone Tower. This mask is vital to beating the boss in Stone Tower, as you the boss is gigantic. Beware though, this mask consumes your magic so if possible, drink a Chatuea from the milk bar (unlimted magic) before the boss battle.
Gibdo Mask-To get this mask, go to Ikana Canyon up by where the house and the dry river are. Follow the river until you come to a cave, and enter into that cave. Go to the center of it, and then who;e the ghost, Sharp, is trying to kill you, play the Song of Storms. Then sneak into the house with the water wheel that now is giving off music. If you put on the Stone Mask, the girl will not see you. Go into the basement and up to the closet. You will be attacked by a freakish gibdo. Please resist the urge to kill it, or you will need to play the song of time and do it all over again. Instead, play the song of healing. The gibdo will be healed into the girl's father. After a conversation, he will give you the Gibdo Mask. This mask will stop Gibdo and Redead from attacking you. You also can see Redead dance. (They're actually pretty good at it!)
Ghot's Remains-You can't where this mask. Get it by beating Ghot in Snowhead Temple.
Goron's Mask-To get this mask, go to the owl in Goron Village. Follow his trail of feathers and get the Lens of Truth. Now go back to where you first found him and use the Lens of Truth to see a Goron Ghost. Follow him to the graveyard and play the song of heaing for him. He will give you the Gorons Mask. This mask allows you to buy powder kegs. You can also transform into a Goron. You are slower but stronger and also have a little set of bongo drums. You can curl into a ball and roll around with spikes (consumes magic) You can enter races with the Goron Mask too!
Great Fairy Mask-To get this mask, go to the laundry pool on the first day as Deku Link and hop across the water to get the lost fairy. Take her back to the Great Fairy in North Clock Town. You are rewarded the Great Fairy Mask after returning the lost fairy. This mask sparkles when you are close to a Great Fairy Fountain or a stray Fairy. Not only that, but the stray fairy automatically comes to you if it is able to. This makes gathering up the stray faires in the temples a piece of cake.
Gyorgs Remains-You can't where this mask. Get it by beating the boss, Gyorg in the Great Bay Temple.
Kafei Mask-To get this mask, go to the Mayors House in East Clock Town shortly after ten o'clock in the morning. Go to the room on the right and speak to the lady(Madame Aroma) and answer yes to her question. She will then give you the Kafei Mask. This mask enables you to start the Kafei and Anju quest by showing it to Anju.
Kamaro's Mask-At night of the first day, exit clock town through the North Exit. Go around the grounds surrounding the ledge that leds down to the Mountains snow. Keep going until you find a man surrounded by tiny boulders dancing on a mushroom shaped rock. If he isn't there, wait a little. Talk to him and play the song of healing. He will give you the Kamaro's Mask. This mask gives you great dancing skills, and you can dance for the practicing twins at night in the West Clock Town to get an extra heart piece.
Keaton Mask-To get this mask, go to the Curiosity Shop on the third day. You can buy it there, but you must have delivered Anju's letter before being able to do this. You can also talk to the curiosity shop owner when getting the Priority Mail in the Anju/Kafei quest to get this mask. Wear this mask near a bunch of shrubs(in either North Clock Town or Milk Road)and slice one shrub with your sword to reveal the Keaton. Answer his questions correctly and get a piece of heart. If you do it again later, you will get 20 rupees.
Mask of Scents-To get this mask, talk to the butler of Deku Palace in the Deku Shrine(to the left of the entrance to the Deku Palace) after beating Odolwa and clearing the monkey's name. You will have to follow him (the bunny hood is recommended to use). This mask allows you to smell different mushrooms to make into potions to cure you when cursed.
Oldolwa's Remains-Get this mask by beating Oldalwa in Woodfall Temple. You can't wear this mask.
Mask Of Truth-Get this mask by completing the Woodfall temple Skultula House and collecting all 30 skultullas. Talk to the man at the entrance once getting all 30, and he will give it to you. This mask gives you the power to hear what animals are thinking. This is a great help in the Dog Race. Just wear it when picking up a dog, and you will find out how they feel. Also, if you ever see a Time Stone, put on your mask and check it for some helpful tips.
Postman's Hat-Get this mask by delivering the Priority Mail(,gotten from the Curiosity Shop owner in the Anju/Kafei quest,) to the postman after getting the Keaton Mask. He will then give you the postman's hat. Look in a mailbox while wearing it to get a heart piece. After that, you get a rupee every time you look in the mailbox, as slow but efficient way to get rich!
Romani's Mask-To get this mask protect the Romani Ranch from aliens on day 1(see bottles guide for more detailed explaination) and protect Cremia from the Gorman brothers on her milk run on day two at 6 PM. Cremia will only do the milk run if you sucessfully guarded the ranch on the first day. If you wear the Circus Leader's Mask, the Milk Run is no challenge, but assuming that you don't have it, you will be attacked by the gorman brother bandits on the run. Your job is to keep shooting arrows(don't worry, they're unlimited) at the Gorman Brothers(not their horses) to slow them down. If you let them get too close, they'll break a milk can. If they break 4 milk cans, you fail. Once you complete the run, Cremia will give you the Romani Mask, as she considers you an adult now.
This mask gives you access to the Milk Bar at all open hours, letting you get a empty bottle, the Circus Leader's mask, as well as allows you to buy the high esteemed Chateua Milk, which gives you unlimted magic power until you play the Song of Time again.
Stone Mask-This is the greatest mask ever! It is obtained by getting a red potion. Then go to Ikana Canyon and jump over 2 fences with Empona. You should see a small circle of rocks, after jumping over the fences. Use the Lens of Truth to see a stranded man. Give him the red potion and he will give you the Stone Mask. This mask makes you invisible to enemies when worn. It also allows you to sneak into other peoples houses(ex: to get Gibdo mask) as well as avoid monsters. Also, when the man on the Great Bay Coast wants a picture of a pirate, just hop on a pirate boat, and you can stand in front of hte pirate and take a pictue. You can use the mask to infiltrate the entire pirate base, as no one can see you with this mask on! Note: Invisible is not invincible.
TwinMold's Remains-Obtained by beating the boss in Stone Tower. Cannot be worn.
Zora Mask-Get this mask by going to Great Bay. Go to the area off the coast where all of the seagulls are right off of the coast. You will find a floating Zora. Push him to the shore and play the song of Healing to get the Zora Mask. This mask allows you to walk under water foras long as you want and swim super fast underwater. You can also use your fins as boomerangs. To top that off, if you press R underwater or B while using your shield on land, you get a magical barrier(like Nayru's Love, only can be turned off whenever you wish!)