Are we talking combos or strings? Well i go through strings from the top of my head.
F-throw->Fair/RAR Bair/Uair (that works depending on their DI. Sometimes it actually makes the "chaingrab" easier...)/ Bouncing Fish/ Airdodgepunish-Vanish
D-throw->Uair/Fair (if they DI away and don't have too high %)/Short BF (yes we are crazy)/Airdodgepunish-Vanish/Bair if you're good
Ftilt->Ftilt/ Fair/ RAR Bair/ HH Needles (can work I guess)/Uair or possible condition an airdodge and punish the laggy landing with stuff / grab
(Weak) Nair->BF (high%)/Dtilt (not true but shield pressure and spacing and stuff) /grab / If you push them off a ledge jab lock (or in sheiks case weak Nair/Bair lock...)
Dtilt->Fair/ Needles/ Uair (from a tipper, kill%, combo) / grab
Utilt->...hope they mess up theitr reactiuon (what they usually do cause no one expects you to hit with an up tilt, usually i hit with the second hit and can follow up with pretty much anything...)
Fair->Fair (obviously...) / BF (low%)/ RAR Bair (ey, stylin?(I still want to make the Bair-plane a thing...)) / Uair/ Regrab (low%)/ Utilt/ Ftilt (swan...)
Jab-combo-ledge-cancel->Nair (true) / Fair (pretty solid... do a nair, best option...)
Airneedles -> Bouncing fish
Fsmash-> Bouncing Fish (My personal favourite, not guaranteed but can work if they mess up. Only low% tho.)
And since I'm the gif guy,
here's the Bair lock and Fsmahs-BF follow up. Everything except BF is guaranteed off of that first hit...