Walkthrough:The Legend of Zelda: Majora's Mask/Xykeb Zraliv/Boss Strategies

Just as a note, as you probably know, difficulty is relative. So you may find a boss way easier or way harder than I say they are.

Dinofols
There really isn't much strategy here, to be honest. Z-target, slash it when it looks vulnerable, and backflip a few times when it's about to breathe fire. Oh, and hold your shield up when you're not attacking so its attacks won't hurt you.
 * Difficulty: *
 * Useful things to have equipped: None

Gekko (Woodfall Temple)

 * Difficulty: **
 * Useful things to have equipped: Deku Mask, Hero's Bow

Phase 1
Just slash it a few times.

Phase 2
Put the Deku Mask on and go into one of the Deku Flower. When the Snapper passes over you, jump up, then cancel (if you turned the Snapper over; otherwise, repeat). Take the Deku Mask off and shoot Gekko (who is now climbing the walls and ceiling). Repeat a few times.

Wizzrobe (Ice)

 * Difficulty: **
 * Useful things to have equipped: Hero's Bow, Fire Arrows if you have them

Phase 1
Take out the Hero's Bow and look around until you find the Wizzrobe. Shoot it. Repeat a few times. When you see it preparing to attack (it will hold its staff back a bit), get out of shooting mode and roll out of the way (or use the Mirror Shield if you have it).

Phase 2
Exactly like phase 1, only now there are a bunch of copies that will run around the room. Ignore this optical illusion and just look for the one that's spinning in place.

Gerudo Guard
Z-target her and hold up your shield. Sidestep constantly. When she does her super-spin-jumpslash move, you can easily dodge it if you are sidestepping. Then slash her. Repeat.
 * Difficulty: **
 * Useful things to have equipped: None

Wart

 * Difficulty: ****
 * Useful things to have equipped: Hookshot, Hero's Bow, Bombs

Phase 1
Look up to start the battle.

Randomly target the mini-Warts and Hookshot them to you, then immediately slash them. Do this until there are several large gaps in the "barrier". When Wart opens its eye and there is an opening, shoot it with the Hookshot or Hero's Bow (Hero's Bow is faster, but Hookshot doesn't require ammo). Repeat several times.

Phase 2
All the mini-Warts will fall off. Drop some bombs (and move away from them, of course) to thin them out, then kill the last stragglers. The main eye will charge around the room (randomly when its eye is closed, towards you when it's open). When its eye is open and you have a clear shot, shoot it with the Hookshot or Hero's Bow. Repeat.

Gekko (Great Bay Temple)
Find Gekko in the mass of Mad Jelly, then jumpslash it. When it goes into a mass on the ceiling, run to a corner as it drops down. When it goes back to the ceiling, shoot it with an Ice Arrow. It will go back to finding Gekko and attacking, etc. Repeat until you've won.
 * Difficulty: ***
 * Useful things to have equipped: Ice Arrows

Wizzrobe (Fire)
This is exactly the same as the Ice Wizzrobe, only Ice Arrows are now effective.
 * Difficulty: **
 * Useful things to have equipped: Ice Arrows

Igos' Servants
As soon as the fight starts, aim a Fire Arrow to the left and shoot one of the shades blocking the windows. Then stand in the light that is provided and shoot the other one. Now, for the minibosses themselves...Attack them when they leave an opening. When they do a large slash, attack them after they do it; if they do anything else, attack before. After one falls, shine light on him with the Mirror Shield. Do the same with the other.
 * Difficulty: ***
 * Useful things to have equipped: Fire Arrows

Garo Master
Z-target him, hold up your shield, and constantly sidestep. Depending on how far away he is, you may dodge his attack by sidestepping. If not, you will block his attack with your shield. If you dodge his attack, he will look around trying to find you. While he is doing this, jumpslash him. Then hold your shield up, since he'll do some spinny thing when you hit him. Sometimes when he's trying to attack you, he'll disappear midway. When this happens, roll forward, turn around, and jumpslash him.
 * Difficulty: **
 * Useful things to have equipped: None

Gomess
Just shoot Light Arrows at it, then slash/jumpslash it. Repeat. That's all there is to it.
 * Difficulty: **
 * Useful things to have equipped: Light Arrows

Odolwa
This fight doesn't have that much strategy. Just slash him when he appears to be open. Sometimes try to shoot him with the bow if you feel like it. The things that'll really do damage to him are the Bomb Flowers strewn around the stage, but it's unfortunately quite difficult to hit him with one since he jumps around all the time. However, there is a somewhat more useful subsitute: the Bomb Mask. If you get close to him, you can use it to inflict considerable damage. However, if you use this, you cannot use it again for a while. Also, if he summons insects, grab a Bomb Flower and throw it in a random direction.
 * Difficulty: ***
 * Useful things to have equipped: Hero's Bow, Bomb Mask

Goht
Using the Goron Mask, roll around the course and try to reach Goht. The spikes that surround you at full speed will damage it. Sometimes it will fall down, and then if you go right behind its back legs and roll into it constantly, you can inflict some major damage on it. It will try to hit you with some electric stuff that is unfortunately quite hard to dodge. As you inflict more and more damage on it, it will get more desperate and start throwing more things to get in your way, including bombs at some point.
 * Difficulty: ***
 * Useful things to have equipped: Goron Mask, Fire Arrows

Alternatively, you can just stand in the entrance and shoot Fire Arrows whenever it passes you. It is impossible for it to damage you unless it throws a bomb near you (which is fairly rare), but it takes a lot longer.

Gyorg
Shoot Gyorg with the Hero's Bow when it's swimming around. Then put on the Zora Mask and use the "R" shield when you get near it to damage it. Then swim back up to the platform (it will often try to eat you when you try to go back up). Later on, it will release several "mini-Gyorgs", but these can be ignored or easily killed.
 * Difficulty: ****
 * Useful things to have equipped: Zora Mask, Hero's Bow

Igos du Ikana
This fight is tough. It required no real strategy, strictly speaking, and solely depends on your skill with the sword. Look out for openings when he starts his attacks, and stay on the defensive. When he detaches his head, put the Goron Mask on and roll around the room for a while. Hopefully, he will stop and put his head back on (I think he'll only do this when you're not rolling around, so just try to do it for a short while), since this move is impossible to dodge otherwise. When he falls, reflect light on him with the Mirror Shield.
 * Difficulty: ****
 * Useful things to have equipped: Goron Mask

Twinmold
There is no strategy here. Just equip the Giant's Mask and slash their heads and tails until they die. That's it. No Z-targeting, no special tricks, nothing. Just slash them over and over again. The design for this boss is one of the laziest I've ever seen. Oh, well, there is one thing you should know. When you start to run out of magic, slash the ruins around the desert and shrink down to grab some magic jars.
 * Difficulty: ***
 * Useful things to have equipped: Giant's Mask

Majora (Fierce Deity's Mask version)

 * Difficulty: **
 * Useful things to have equipped: Fierce Deity's Mask

Phase 1
Shoot a sword beam at the mask, then jumpslash it. Repeat several times. Partway through the fight, you will have to fight the other four masks in addition to Majora, but these are easiy killed with a single sword beam each.

Phase 2
Shoot a sword beam at it when it stops, then jumpslash it. Repeat.

Phase 3
Same as phase two. Same as phase one, now that I think about it :P

Majora (Non-Fierce Deity's Mask version)
Coming as soon as I actually attempt this myself :P