Okay, so the fact that I can write a boss guide for Metroid Prime mainly comes from my experience. I'm going from memory, and the fact that I haven't played this game doesn't exactly help. Then again, this is a great game, so I remember it well enough to bother writing this in the first place, savvy?
So, let's go!
Boss: Parasite Queen
Difficulty: Beginner (to the point where if you do know how, you can beat it without even scanning it!)
What to do:
Basically, you simply scan it to find out that it's weak point is the mouth, and just missile it. Charge shots also work. However, when the force field is in front of it, the shots will miss. Not hard in the least.
Boss: Flaaghra
Difficulty: Easy - Moderate
What to do:
There are a few different methods to beat this thing. The basic idea is to simply hit the solar panels with either Charge shot or Missile, then hit the bomb slot with... a bomb. This can be done in two fashions: 1) lock onto Flaaghra, then rotate around the boss whilst within range of the panels then hitting them as you pass. 2) a little trickier, but you can hit two consecutive panels very easily if you manually aim.
Also, it's recommended that between every 2 panels (there's only 4 anyway), you'll want to stun Flaaghra. This is done by either repeatedly hitting it with charged shots followed by a Missile, or by waiting for it to create that flora block and hitting it then with a Missile.
Ability/Weapon/Item: Varia Suit.
Boss: Sheegoth
Difficulty: Easy
What to do:
Like many bosses in this game, there's usually more than one way to take it down. Though Sheegoth is considered a mini boss in some ways (and sadly, yes it eventually becomes a normal enemy.), it has enough to it to become an actual boss.
First off, scan it. You'll learn if you read it that it gets weakened from being hit with energy to it's spikes. So, you'll want to get an opening to actually hit it. Fire normal power beam shots, or charged shots and simply wait for it to hyperventilate (while dodging ice shots and ice breath; both of which can and will freeze you). Then just fire Missiles at the mouth to take it down. Another option, is when it hyperventilates, you can also bomb the belly region. A bit more hazardous, but does about the same thing.
Weapon/Ability/Item: Wave Beam
Boss: Thardus
Difficulty: Moderate
What to do:
So, this one's a bit more of a challenge this time, and basically features a gigantic living mass of rocks. Oh, and did I mention the rocks are infused with Phazon? No? Well, now you know.
This is a relatively easy fight depending on how you look at it. The basic idea here it to blast off the phazon sections of it's body. However, Thardus has some nasty attacks. It can hurl boulders at you (phazon enriched, I might add), and is capable of sending a stream of ice at you (on the ground). To evade most of these, I find an interesting strategy can actually be found at the back of the arena. Those small rock formations aren't just for show; you can climb them. Basically, stay here and you can handle it for the most part. However, be ready to approach it when it goes into "Blizzard Mode" at which it'll concoct a deadly blizzard making it harder to find him. This is where you'll have to actually go up and fight it. It'll also roll around a considerable amount after each segment is destroyed. However, in order to even know about each segment, you'll need the Thermal Visor to actually see them.
I find the Wave Beam works well here: it has a limited auto lock on that I find rather useful for the boulders.
Weapon/Ability/Item: Spider Ball
Boss: Omega Pirate
Difficulty: Moderate - Hard (that's if you don't quite know what you're up against
What to do:
The irony of this game is making you think that it's not very difficult; up until you fight this thing. I sware, you may lose a few times before beating him, but it is possible to beat it. There's a few tricks to getting him right where you want to.
This fight is divided in three sections (Well, two, but I still consider the second part a two parter. Just read...). The first part involves actually blasting off it's phazon plates. Fire a Super Missile for these. You'll need four for each of it's limbs. Stay a reasonable distance from it; to close, and it'll pound you, to far and it'll launch missiles at you. However, staying at just the right distance will only make it ground pound. When it's not charging (holding a yellow sphere in front of it's hand), that's the queue to fire.
Once it's plating it gone, it'll become invisible (although, you'll get to see it's phazon enriched veins just prior to), and send in re-inforcements. You have two options here: quickly kill the troopers and then look for the boss, or flat out ignore the troopers and search out the boss. If you decide to kill the troopers, simply wait a moment and the Pirate will emerge at a phazon pool. This is where you attack it. Super Missile or charged Plasma Beam work well either way.
Interesting hint: it is possible to defeat this guy in exactly one round; when he goes invisible, stay near one of the pools and wait for it to appear. Basically, if you can time your Plasma shots well enough, he should appear twice, and you should be able to take it down quicker this way to.
Other advice: Try to kill it within the least amount of rounds possible; the more it takes, the more troopers will appear. We don't want that now do we?
Weapon/Ability/Item: Phazon Suit.
Boss: Meta-Ridley
Difficulty: Moderate - Easy?
What to do:
Well, it's finally time to take this dragon down. Probably one of the most deceiving of all the bosses in this game. Simply because you can exploit a weapon to kill him by quite literally holding down the [a] button. No, I am not kidding.
Basically, you're main goal is to hit him in the chest with Plasma Beam shots. Once he lands, you have two options: hit him with Boost Ball for him to immediately go into Land mode, or continue on to whittle down his health.
Once he's "grounded", he'll dash at you. Time your charged shot effectively enough and you'll get the chance to hit him with Missile after Missile. However, there's an easier way. If you've found the WaveBuster, simply switch to wave beam and fire the beam combo. And just hold it. This does work. Cheap, but it works.
