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Smash Apprentice
For sure, Kirby is the most disgusting character, and would have to be at the top of any tier list. Then it's a close call between Pikachu, Ness, and Fox.
Pikachu's got a lot of aerial priority, and amazing recovery. Also, his grab is among the fastest, with a long-distance throw to match.
Ness' third jump is pitiful in all honesty, but his yo-yo and grabbing/throwing capabilites are a force to be reckoned with. Coupled with that nasty spike and a reflecting homerun bat, he's surely in the running for top tier.
Fox is your all around good character. His throw's aren't the best, and his recovery leaves somewhat to be desired, also having no 'real' spike (shining seems to work well, however) are all drawbacks. His footspeed, rivaled only by Cpt. Falcon (who runs circles around anybody), and his simply sickening down smash, along with juggling and arguably the most useful ranged attack in SSB64, he's lookin' pretty good in my book.
So, the top tier would have to consist of Kirby, and I'm going to go with Ness. This of course makes Fox and Pikachu top of the upper tier.
Also considered for upper tier would be Link, and Yoshi.
My reasons for this are good ones.
Yoshi. I realize Yoshi's not much of a crowd favorite, but he's got a lot of potential. Lacking a third jump is compensated by having that annoyingly uninteruptable second, egg throwing is dirty, great spike, best of the three ranged grabs, minihop+dair tears stuff up, (especially DK), best shield in the game, great rolls, up tilt has amazing priority, decent run speed.
Link is a tank, but he's slower than most characters. He's more than capable of fighting at a distance, and has the only disjointed hitbox. Horrible recovery, but he's got excellent throws and is very heavy. You just can't argue with his uair, it has enormous priority and knockback. Boomerang can be thrown to hit like twelve different places from any position, making it extremely versatile. He's Link for crying out loud! He's the Hero of Time! That's worth big points.
In all honesty, though, (in order) Fox, Pikachu, Yoshi, and Link are my upper tier.
Lower tier, We have Cpt. Falcon, Jigglypuff, Mario, Luigi, DK, and Samus left to choose from.
Samus tops the lower tier: Good recovery, amazing spike, great aerial priority, POWERFUL throws (although the grab is hard to land) great rolls, nigh-unstoppable up+b, and let's face it; Samus is a babe.
Cpt. Falcon. He runs the fastest. His spike is slightly delayed, where most in SSB64 are not. Great up+b attack, uair is to be respected. Hind throw is good. Rolling is poor. lacks any range, but is fast enough to compensate. All in all, good character, but not really up to par.
Jigglypuff. The little ball of fury kicks some serious trash. Jigglypuff has NO RANGE, but makes up for it with HUGE priority. Pound has all-powerful priority; don't mess with it. Nice horizontal recovery, but NO vertical. Simply amazing edgeguard. Hind throw being near-horizontal means buisiness. Dair has good priority and can easily be combined with a Rest for an easy KO. Bair, again good priority and knockback isn't bad. I wish I could put Jigglypuff in a higher tier, but his recovery is just too easy to abuse. Plus taunting with Jigglypuff is simply priceless. This can draw ANYONE into a blind rage.
Luigi can recover from almost anything, and his throws are sound. Good rolling range/speed, amazing priority/range on his forward smash/up smash, great tilts, and the only damaging taunt in the game.
Mario. A lot like Luigi. He's a bit lighter on his feet, and can't jump as high. Throws are good, grabs are good. Recovery not as good. Horribly long taunt. Nice uair. Up smash and down smash are very good. Also nice tilts. Mario is a very sound character, but he doesn't do any one thing remarkably well. Again, should be higher on the list.
That's all for the lower tier.
DK makes up the very lonely and shameful bottom tier.
The guy's far to big a target, and has absolutely no vertical recovery to speak of. His grabs/throws are excellent, but he falls short in melee comabt with most anyone. Dig the tie, however. A shame he wasn't better designed.
Once more for the viewers at home:
**TOP TIER**
Kirby
Ness
**UPPER TIER**
Fox
Pikachu
Yoshi
Link
**LOWER TIER**
Samus
Jigglypuff
Captain Falcon
Luigi
Mario
**BOTTOM TIER**
Donkey Kong
Just a note, I have been playing SSB64 almost nonstop since it came out 6 years ago. I have two brothers that play with me and I have a lot of experience with a lot about the game. However, I am biased and stubborn, so you don't have to accept my tier list if you don't want to.
Pikachu's got a lot of aerial priority, and amazing recovery. Also, his grab is among the fastest, with a long-distance throw to match.
Ness' third jump is pitiful in all honesty, but his yo-yo and grabbing/throwing capabilites are a force to be reckoned with. Coupled with that nasty spike and a reflecting homerun bat, he's surely in the running for top tier.
Fox is your all around good character. His throw's aren't the best, and his recovery leaves somewhat to be desired, also having no 'real' spike (shining seems to work well, however) are all drawbacks. His footspeed, rivaled only by Cpt. Falcon (who runs circles around anybody), and his simply sickening down smash, along with juggling and arguably the most useful ranged attack in SSB64, he's lookin' pretty good in my book.
So, the top tier would have to consist of Kirby, and I'm going to go with Ness. This of course makes Fox and Pikachu top of the upper tier.
Also considered for upper tier would be Link, and Yoshi.
My reasons for this are good ones.
Yoshi. I realize Yoshi's not much of a crowd favorite, but he's got a lot of potential. Lacking a third jump is compensated by having that annoyingly uninteruptable second, egg throwing is dirty, great spike, best of the three ranged grabs, minihop+dair tears stuff up, (especially DK), best shield in the game, great rolls, up tilt has amazing priority, decent run speed.
Link is a tank, but he's slower than most characters. He's more than capable of fighting at a distance, and has the only disjointed hitbox. Horrible recovery, but he's got excellent throws and is very heavy. You just can't argue with his uair, it has enormous priority and knockback. Boomerang can be thrown to hit like twelve different places from any position, making it extremely versatile. He's Link for crying out loud! He's the Hero of Time! That's worth big points.
In all honesty, though, (in order) Fox, Pikachu, Yoshi, and Link are my upper tier.
Lower tier, We have Cpt. Falcon, Jigglypuff, Mario, Luigi, DK, and Samus left to choose from.
Samus tops the lower tier: Good recovery, amazing spike, great aerial priority, POWERFUL throws (although the grab is hard to land) great rolls, nigh-unstoppable up+b, and let's face it; Samus is a babe.
Cpt. Falcon. He runs the fastest. His spike is slightly delayed, where most in SSB64 are not. Great up+b attack, uair is to be respected. Hind throw is good. Rolling is poor. lacks any range, but is fast enough to compensate. All in all, good character, but not really up to par.
Jigglypuff. The little ball of fury kicks some serious trash. Jigglypuff has NO RANGE, but makes up for it with HUGE priority. Pound has all-powerful priority; don't mess with it. Nice horizontal recovery, but NO vertical. Simply amazing edgeguard. Hind throw being near-horizontal means buisiness. Dair has good priority and can easily be combined with a Rest for an easy KO. Bair, again good priority and knockback isn't bad. I wish I could put Jigglypuff in a higher tier, but his recovery is just too easy to abuse. Plus taunting with Jigglypuff is simply priceless. This can draw ANYONE into a blind rage.
Luigi can recover from almost anything, and his throws are sound. Good rolling range/speed, amazing priority/range on his forward smash/up smash, great tilts, and the only damaging taunt in the game.
Mario. A lot like Luigi. He's a bit lighter on his feet, and can't jump as high. Throws are good, grabs are good. Recovery not as good. Horribly long taunt. Nice uair. Up smash and down smash are very good. Also nice tilts. Mario is a very sound character, but he doesn't do any one thing remarkably well. Again, should be higher on the list.
That's all for the lower tier.
DK makes up the very lonely and shameful bottom tier.
The guy's far to big a target, and has absolutely no vertical recovery to speak of. His grabs/throws are excellent, but he falls short in melee comabt with most anyone. Dig the tie, however. A shame he wasn't better designed.
Once more for the viewers at home:
**TOP TIER**
Kirby
Ness
**UPPER TIER**
Fox
Pikachu
Yoshi
Link
**LOWER TIER**
Samus
Jigglypuff
Captain Falcon
Luigi
Mario
**BOTTOM TIER**
Donkey Kong
Just a note, I have been playing SSB64 almost nonstop since it came out 6 years ago. I have two brothers that play with me and I have a lot of experience with a lot about the game. However, I am biased and stubborn, so you don't have to accept my tier list if you don't want to.
HAL knew they made him too broken and when they tried to m=balance him in SSBM they neutered him. 
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