Thinkaman: Do you mind if I use pieces of your post(s) as the summary for Snake?
If I posted it, it's public domain. Go nuts.
EDIT: Can we agree on 55-45 MK, and 70-30 Snake
Lol, nope, it seems we cannot agree. 70-30 Snake is too extreme, given Jigg's damage-building advantage and decent gimping ability that forces Snake into playing safe. His u-tilt and high weight still give him the advantage, but it's not a 70-30 advantage. Based on playing Joker, it's 60-40; a player as good as Joker would have been able to consistently two-stock me with a 70-30 or better matchup. I also beat Karmacide first round of brackets back at NO KOAST, who I consider to be on my skill level... 70-30 would have meant I had less than a 10% chance of doing that.
And everyone knows how I feel about Meta Knight's matchup.
This is true. Besides Diddy, it's Jigg's best matchup in the top half of the roster.
Falco has trouble killing Jigglypuff. Honestly, he's like a Fox that can't kill! Sure, he has some lasers and chaingrabs and a great ground game and blah-blah-POUND!
Oh, sorry Falco, I was too busy being in the air to care.
Against Falco Jiggs does need to go higher than usual, due to Falco's excellent jumping ability and lasers. Be more mindful of your jumps, and be on the lookup for uairs (like Fox), but otherwise it's smooth sailing on the approach front... something NO ONE ELSE can say against Falco.
Shine is annoying, but a baited shine lets Jigglypuff do terrible things to the bird.
Falco's recovery is like a carnival for Jigglypuff, but don't mess it up. Always nair side-B. Then nair it again, and again. Eventually his faster speed will probably get around you, but the extra damage is great. Against up-B just dair him. He'll have to up-B again immediately, so leisurely fair or bair him in whatever direction you want. (Under the stage is always nice.)
I don't think I've ever lost to a Falco, actually. All the better ones go other characters against me, and the rest sit frustrated and confused as they get 2-stocked by this thing that they can't kill.
Remember, Falco is pretty light. It's worth saving fair for that early kill, no need to go all out and then have to resort to dash attack, you don't want to be on the ground anyway.
Being very low to the ground against Falco is, momentarily, a really good position though. If he lasers you can land into a duck (otherwise a gimmick) and if he jumps, you can land and shield-grab whatever he does in the air. This will probably get him off stage to boot!
And yes, planking is great against space animals. I don't really have any experience planking, but it's fairly obvious.
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Which brings us to DDD...
DDD is a fight of endurance. I actually enjoy it quite a bit, though the matchup is not in Jigglypuff's favor by any means. I'm not sure if I would quite call it 60-40, but it's at least 55-45 DDD.
I am going to once against disagree with PND and say that approaching DDD from the air is always the way to go. In this battle of endurance, where Jiggs is the easiest character in the game to kill vertically and DDD is the hardest, Jigglypuff can not afford any of DDD's absurd 18% damage grabs. DDD's u-tilt is a reliable kill, although not as unavoidable as Snake's... similarly, Jigglypuff's aerials are pretty easy to land on DDD. This fight is all about damage.
First, burn fair. You have much less throw damage to count on, and aren't going to be able to fight DDD long enough with just other aerials to get a low fair KO, sorry. Try to freshen up your fair at extremely high percents (you can bair or dair waddle doos easily!), but otherwise accept that you will probably be killing with dash attack. Remember, if you burn fair but fail to take the stock first anyway, it matters little since your respawned fresh fair can easily finish him to even the score.
Second, DDD's bair is scary. It comes out fast and he can repeat it fast. You need nair if you are going to break through, bairs and fairs alone will not beat DDD!
Third, play cautiously at low percents. DDD's ridiculous weight and fall speed combination means he won't go very far when you hit him. Many moves, especially those that scale with damage, will not push him far, and allow DDD to retaliate. Remember what we said about weight difference? Trading hits is another way to say "lose" is this matchup.
Fourth, harass the grab out of DDD off stage. Know how to best deal with up-b: Your main goal should be to keep the free damage train going as long as possible.
Fifth, rest is just too risky. Except for drill rest at appropriate percents (and not one sooner!), don't rest. Maybe you can kill him early out of up-b or something flashy, but I really don't care. F-smash and down-B say hi.
Sixth, his inhale kills Rollout. Such a risky move has little place in an endurance match anyway.
Otherwise... you just have to outwit, outplay, outlast. Or something.
Edit: Can you double or triple u-tilt DDD at low percents? I don't think the fat tub of lard has ever let my Jigglypuff in early enough to try, but I know other characters have a fun time with him...