How to deal with Jigglypuff? Her aerials are very annoying coupled with her side-b.
What can DK do to take advantage?
All you need to do is use your tilts, Bair, and Uair to trade with or beat her aerials cleanly. Due to the weight difference, you can lose like 2 out of 3 times and still come out ahead. The only real way you can lose is if you get hit by rest consistently or get edge guarded mercilessly. Both of those scenarios are more along the lines of getting outplayed as opposed to the MU being difficult, so just practice your spacing.
What's the most optimal damage you can get when you break a shield before 9-wind/full charged fsmash will kill?
Grab -> Jump CUT -> Bair -> Up B for like 60%. You could squeeze in a Pummel and an AC Nair or risk a Dtilt trip for an extra 10% too, but that is probably too much. You can also do it without the Bair and probably have to on certain characters at certain %'s.
I was wondering what the optimal follow ups at low percents are when dk get a grab. When I get a grab at 0, it seems that the only true combo I can get out of cargo upthrow is up air, but I don't want to stale it so it kills as early as possible. At mid percents I normally go for cargo upthrow > nair > bair or upB. And at high percents I go for up air obviously because it kills. Just not sure what is optimal for the 0-10% range. Let me know what you guys prefer to do when you get a grab at low percents
At very low %'s opponents can mash out while you jump, so it is better to just to grounded CUT to Uair (or Usmash on certain characters). If for whatever reason you really don't want to Uair and Usmash won't combo, you could just do CBT instead for 12%. If they are slow mashers, you can jump and do w/e you want as normal including Bair and Up B.
How do you do the ding-dong at high percents? FThrow into Uair seems to work beyond 80% when I watch streams, but I don't know how to do it.
It is just good timing and not having too much rage. You have to start the throw as early in your jump as possible and double jump as soon as you can. Doing both of these leaves them close enough to you to still combo at higher %'s. With too much rage it won't work at higher %'s, but can KO even earlier.