AC dair rest
It is possible to autocancel puff’s dair and combo to rest at low %s.
Dair’s last hit is on frame 26 and it autocancels as early as frame 39. This means that if you hit with the last hit of dair and can land on or very soon after frame 39 and the opponent is still in hitstun after your 4f of landing lag (for a total of at least 17f of hitstun) then you can combo AC dair to rest. You need 23f of hitstun for grab. You can look up what % that is per character here.
The frame advantage of AC dair happens to be effectively identical to L-canceled dair HOWEVER with an AC dair you maintain enough control to steer puff over the opponent regardless of their hitstun animation, allowing you to combo dair to rest at low %s. AC dair will combo to rest on spacies from as low as 20% after the dair. Remember, spikestun is useful because it allows us to hit-confirm based on the predictable animation but with AC dair's low profile and extra drift control that is not necessary.
Similar to the spikestun setup, the last hit of dair is the only one that’s important and any hits before the last one increase the likelihood that your opponent will SDI out of the combo. The biggest drawback to AC dair is that it is much more difficult to execute than an L-canceled dair. It’s difficult to set up and it’s difficult even to see how close/far you are from perfect without using frame counter. For the time being, AC dair rest is not worth practicing for tournament use. But it is sick AF.
* SH DJ dair FF
* FH dair FF
* shield drop DJ dair FF
* from a late double jump
* from the ledge
* SH ff dair off top plat
(you also can reach this height with SH DJ from side plat or a FH DJ DJ)
* fall through slight delay no ff off top plat
(you also can reach this height with FH from side plat or a FH DJ)
Obviously other intermediary/stage specific setups are possible and will require different variations on timing/ff. The setups listed above are only the most obvious reference points.