Question
What are the best strategies for defeating the bosses in the Thunder Dragon's Boss Battle challenge?
I want to be able to survive long enough to get the Hylian Shield at least but it is difficult since we can't use any other items in our pouch except a shield.
Answer
The strategies I go over here will be primarily from the perspective of someone playing in Hero Mode. You can still use these strategies when playing in normal mode, it's just that it's not as essential since it is a lot easier to survive since you may gain hearts still and you don't take extra damage.
Preparation:
Before you consider trying to take on this challenge, make sure the items you can take with you are upgraded to their strongest versions. You want to be able to finish this as quickly as possible and having the strongest weapons will help with that. So you should have the complete Master Sword with you, (at a minimum) the Goddess Shield (the Sacred Shield upgraded twice) and the Sacred Bow (the Bow upgraded twice). It will also help if you come in with the maximum bombs and arrows, that way you won't be searching for them when you need it.
Although you can't use items during the challenge, you can use them just before. So certain items that give buffs over time can still have their effect as you enter the challenge. For maximum effectiveness, you should bring with you the Guardian Potion+ (the Guardian Potion infused once) with the Potion Medal. Just before you start the challenge, drink the Guardian Potion+ that way you'll have six minutes of invulnerability. This will give you enough time to save your hearts for the most difficult bosses in the beginning of the challenge. Optionally, you can also take a Stamina Potion+ (the Stamina Potion infused once) too but you really won't need it.
The first boss you choose should be the most difficult boss available that way you make good use of the Guardian Potion+ if you're expecting to take a lot of hits:
When playing the normal mode, I personally found that Koloktos was probably the most difficult of the bosses to not get hurt in. Some of its attacks are just hard to anticipate and prepare for since it has a lot of range and you have to be close for them to come out. Unless you don't mind a long battle waiting for the right attacks to come out, I would recommend doing this one first. Otherwise, it's your choice here. Keep in mind that if you come in using the Guardian Potion+, you don't want to waste too much time.
When playing in Hero Mode, I would strongly suggest you do the Horde Battle first (no exceptions). This is probably the most time consuming battles you'll have to go through and so many ways to get hit. They aren't the hardest enemies in the game but there's so many of them and it is easy to get surrounded.
General Strategy:
Your primary concern for this challenge above all else is to survive taking as little damage as possible. This might not be too much of a problem when playing in normal mode since you can still find hearts in certain places but it is absolutely essential when you're playing in Hero Mode.
Your shield is your lifeline here, use it. If you're not planning on attacking an enemy, you generally should have your shield out at all times by shaking the Nunchuk. That way you can't get caught off guard and take a hit when you're not paying attention. If you see the attack coming, perform a Shield Bash just before it connects. Your shield won't take damage and it will usually leave the enemy stunned for a second so you can counter.
If your Sacred Shield is getting low on durability, stay away from the enemies and their attacks until your shield fully repairs itself. The last thing you want to have happen is to have your shield be destroyed. Of course if you already have the Hylian Shield, you won't have to worry about this.
The Beginning:
Ghirahim
For the first part of the battle, he will hold out one hand to try to grab your sword. If you swing your sword right into his hand, he will grab it. To get him to release it, just flick the Wiimote up. Hitting him can be pretty easy. Just hold out your sword in a direction (e.g., to the right, the left, upper-right, etc.) so he will point his hand in that direction. When he does, flick the Wiimote in that direction again so your sword swing will come from the opposite direction. Repeat until the next part of the battle.
At this point, he'll pull out a sword to finally fight now. He has a couple of different attacks here. He will summon darts and shoot them at you. These are easily avoided but could also be knocked back at him. They don't seem to affect him though. He will also teleport around the room every once in a while, some times right next to you. When he does this, be sure to welcome him with a Spin Attack. This will stun him so you can follow up with more hits. He will also charge in at you and swing with his sword. You can pull a Spin Attack here to hit him when he's close enough. The only catch is that the spin has to be right into him. If he charges in at you to your left, you need to perform a Spin Attack spinning to the right. Otherwise, you can Shield Bash at the right time and counter. Repeat until he's dead.
Scaldera
You'll need to get your bombs ready for this battle. When Scaldera is glowing orange with lava, he is invulnerable to your attacks. You need to wait for him to stop glowing. Just run up the ramp until he stops. When he does, turn around and throw a bomb at him. It will knock him back down the ramp, follow him. When he recovers, he will breathe in to blow some fireballs at you. As he does this, throw a bomb at him so he will eat it. This will stun him allowing you to attack his eye. Repeat this until he is dead.
At some point after you have hit him enough times, he will run up the ramp high off the ground. When he does this, just let him run above you up the ramp. He can't hurt you. He will roll down the hill once he reaches the top but you should be able to easily dodge him. When he reaches the bottom, he will breathe in for the fireballs, you know what to do then.
Moldarach
The Imprisoned
The Middle:
Koloktos
Tentalus
Ghirahim
The Imprisoned
Later On:
The Imprisoned
In this battle, things get a little complicated. This time around, he grew a tail and can fly later on. Again, I still find it safest to go straight for his head however he will always shake you off. Before you go on to jump onto his head, switch to Groose to hurl a bomb at him. That should stun him long enough for you to be able to jump on his head to drive the spike down.
Doing this, the imprisoned will start to fly. Not a problem though, fortunately Groose will have a bomb ready. Shoot him down. It will knock him into the ground in the center. Get down there and knock the spike into his head.
He will start to fly again but Groose's supply of bombs will be blocked making it unusable. fortunately you still have a perfectly working catapult. Climb up to the top and ride that catapult by shooting yourself onto the imprisoned's head. Once you get there, drive the spike in his head one more time to finish him off.
Horde Battle
I consider this battle mostly just a race than a real battle. Most of the enemies you see here will be Bokoblins (and other variations) and can be killed in a single swing of the sword. You don't want to waste too much time fighting off the endless streams of them, you want to make it to the end as fast as possible.
Until you are stopped by a wall and forced to fight, you should be sprinting your way down the kill dodging the enemies that get in your way (remember, you can't have your shield out and sprint at the same time). Try to pick up Stamina Fruits on your way down to minimize the time you have to walk and recover.
When the time comes to fight, you should take care of the horde first. Don't even go near the "specialist" enemies yet until you've dispatched the weaker ones. I find it easy to let them bunch up, run up to the group and do a Spin Attack and step away. Let them bunch up again and repeat. Once you've taken care of the "dumb" Bokoblins, you can go after specialists. Just use your instincts here, there's nothing special about these enemies than what you've already encountered. There is a blue Bokoblin that takes an unusual amount of damage but that's about it.
Ghirahim
This battle is about patience. Just about all the attacks he has are counters or must be countered. You're not going to win this battle by blindly flailing around your sword.
The first phase of the battle should be simple. The goal is to knock him down off the platforms so you can perform a Finishing Move on his weak point, the diamond in his chest. In order to do that, just wail away at him until you knock him over the edge. Every once in a while, he will attack you. He will always make an audible noise and change stances before he does so. When you see him do this, dodge back or pull out your shield. After he swings, just continue swinging away.
After you knock him down the first time and he gets close to the edge, he will start to hold out purple flames from his hands. If you hit them, he will counter so you need to not hit them. Take your time here and slow down, there's no rush but don't take too long. Hitting him three times will move on to the second phase of the battle.
To kill him quickly here, get close enough and try to do straight stabs at him. He will parry your stab and will attempt to counter. When he does, shield bash at the right time to quickly stun him. Once stunned, stab him in the chest. After this, he will jump back and shoot off his own "skyward strikes" at you. Just dodge these or knock them back, hitting him will stun him even longer. Just repeat until the last phase in the battle.
In the last phase of the battle, he will materialize a huge sword to attack you with. The goal is to break his sword so you can hit him in the chest two more times. Here you can take your time a little bit here. If you swing at him or Shield Bash his attacks at the right time, he'll hold out his sword to block your attacks. You'll want to hit the sword in the same exact spot four times to expose the crystal inside it to destroy it. If you don't, he will counter and repair his sword.
You can only swing at it perpendicular to how he's holding it. So if he's holding it vertically, you need to swing at it horizontally. Make sure you swing at it at the side where you last hit it. If you see the broken side on the right, swing at the right. After the sword is destroyed, you can stab him in the chest.
Demise
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