saberopus
Likes Kittens. Eats Fluffies
Posts: 12,306
Get on the ground, with it across from you (as far away as possible, but as long as you're not touching, it's ok). This isn't that hard because when you land, it usually lands, too. You have to spin jump/screw attack towards it (generally OVER it) without touching it, b/c whenever you screw attack into each other (or even bump into each other) YOU take the damage, and it's quite a bit. So, spin jump over it. It will also spin jump, once you take off, to catch you, so just do one or two spins, with the goal of landing behind it (ala where it was before you jumped). At this point, it will almost unfailingly land, also, in order to shoot you, and it usually lands right where you took off from. Basically you swith places, and if you time it right (and it's not that hard after a few tries) you can do it without taking any damage. Then, of course, once you've both landed, it will turn and shoot you, so your goal should be to get off the first shot and immediately transition into another spin jump, the opposite of your first. During these jumps, you need to be holding down 'B', btw, in order to charge your shot, b/c (I'm pretty sure) the uncharged shot does no damage, and missiles require you to hold down more buttons, which can affect your movement ability.
Formula = Spin Jump while charging, then Land and Turn and Fire As Fast as Possible, then Spin Jump while charging... etc etc.
After a few times, it's possible to do this without taking any hits. However, if you land too close to the SA-X, when you try to do your spin jump, you'll bump into each other and you will take damage.
(I'm bored and feeling the need to be overly helpful, hence the long-windedness)
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After you hit it... I'd say about 10 times with the charged shot, it will morph into some giant slobbering monster... which is extremely easy to kill. It just does an arcing jump and tries to land on you, but it's a bit slow, so just move as soon as it jumps, and then turn and fire (at where you were just standing, basically) once it lands. It only takes about 5 hits.
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Unfortunately, then it changes into the large Core x, you know, the gear-looking thing. This is one of the ones that float around until a little port opens and it fires at you. And, as you know, you can only give damage by hitting that port. Soooo... just jump around, avoid it, pick up the stray floating X if you can, and hit that port... it's actually the hardest part IMO, because it's shots do a shazbot-load of damage... it's annoying as hell to get that far and then die.
Annnnnnd after that you fight the Omega Metroid, which isn't that hard. Just run up and shoot at an angle to the upper right as many times as you can (single shots DO do damage) into its torso/stomach until it's about to swipe you, then run back. Lather, Rinse, repeate.
