Some crazy true combos
1.
Weak hit falling Uair - full jump, double jump, Fair - Tipper Fair
This is a kill combo, and works from around 50 to 73% on Marth in Training mode.
2.
Falling Uair - fulljump dbljump Fair - DS (up b)
That is really good at mid percents and kills around 55%!
3.
Weak hit falling uair - dbl jump weak hit uair - up b
78-92% true combo on Marth
4.
Weak hit Sh rising fair combos into up b from 53 to 68% and can kill!
5.
Weak hit falling fair into tipper fsmash at 23 - 53% on marth, but after 50%, seems to require dashcancel fsmash or absolute perfect spacing. Probably a good idea to start dashcancel fsmash as early as 43% though.
6.
Weak hit falling fair to tipper ftilt at 16-56%
7.
Weak hit Falling fair to dtilt 7-47%
8.
Weak hit Falling fair to tipper sh fair 40-86%
9. Falling Nair to fsmash 0-30%+, getting harder after 30.
10.
I don't think this is news to anyone, but if dair stage spikes without a tech, it leads to guaranteed kill setups starting around 60%, with either fsmash, then usmash, then uair or bair.
Doing more testing...