I know someone was high on weed while adding Jigglypuff to SSBB.
He was so damn flawed it didn't even make sense, I love Jigglypuff (my ABSOLUTE FAVORITE), but geez, he was a joke on Brawl.
-All of his smash have a lot of starting up time (and are so easily outclassed by Kirby/Meta Knight) and are really weak
-slowest running speed in the game
-lightest weight in the game meaning easiest to kill
-has horrible range
-has a hard time killing enemies
-has almost no safe moves
You take all this to account and it can honestly make you laugh, cuz it's just sick how horrible Jigglypuff became in Brawl. I still love him and use him a lot, it's just, SSB4, needs to really bring Jigglypuff back to how he was in Melee (and just keep the minor improvements he had from brawl, like better Rollout, etc.). Other than bringing Jigglypuff back to how he was on Melee, Jigglypuff was definitely in his prime on Melee, easily one of the best. I think I can think of some other things they can do to improve Jigglypuff.
Strengthen his ground moves and make them more reliable.
-Make Sing useful, Sing is so useless, which is a shame since that's Jigglypuff signature attack. Either make Sing like it was in SSB64 (increase range) or let Jigglypuff WALK with Sing, also, have opponents sleep for a little longer so you actually have a chance to attack that said opponent, it's a joke how people can immediately wake up.
-Rest needs to be as strong as it was in Melee. If they are going to keep it nerfed as it was on Brawl, at least give a good side effect, like maybe Jigglypuff recovers 20% health, that's the least they could do.
-Shield needs massive improvement. It's sick how Jigglypuff has a pretty horrible shield, and then he also dies when it's cracked. Either give Jigglypuff a giant shield that's hard to break, or give off an explosion upon impact on breaking the shield, or just remove that thing period. I know this is probably not a MAJOR problem, but it's still an annoyance that needs to be fixed imo.
I'd make Pound slightly stronger, like by 2% or 3%.
-This may be cheesy, but I have always thought Rollout can be more like it was in the games. Like everytime you use Rollout and it connects with an object, it gets stronger by like 1% or 2%.
Please give Jigglypuff a better Final Smash... Puff Up made my brain implode, it was just... so... no. Just no. They could of used something like Hyper Voice (which would be a LOT better), or maybe something like Perish Song.
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This is all I can think of from the top of my head. Making Jigglypuff like he was on Melee, would already be a major improvement in itself from Brawl (hoping Jiggs will does well with SSB4's physics), those were just some improvements I can think of from my experience with Jiggs. I'm pretty sure the more experienced Jigglypuffs can probably list a lot more things and ways to improve him, but yeah this is just my thoughts and what I hope to see. Hoping to see Jigglypuff return strong and ready to clap a *****.