My go to combos for all variations (1 bar)
Note: For combos with the tiny step needed, you can "run xx 21" instead of "dash > 21" to make it easier, but it's still able to be done with a dash. (Dash is normal dash, not reptile dash)
low to overhead (14f) :
b3 xx db2 EX > njp > dash > 21 > f412 xx bf4 (29%) (may need to take a tiny step before njp depending on distance)
b1d4 xx db2 EX > njp > dash > 21 > f412 xx bf4 (32%)
overhead, neutral on block, easy hit confirm (10f):
b2 > f211+3 EX > tiny step forward > njp > run xx f412 xx bf4 (30%) (if you have have trouble landing the 2 in f412, do f41 xx bf4 for 28% instead)
mid, overhead, punish (8f)
f41 xx db2 EX > njp > dash > 21 > f412 xx bf4 (34%)
long range mid, whiff punish (12f):
f21 xx db2 EX > njp > dash > 21 > f412 xx bf4 (31%)
f211+3 EX > tiny step forward > njp > dash > 21 > f412 xx bf4 (33%)
I take the tiny step in every combo except the b2 one. I don't tap forward, I hold it during the db2 EX animation or the f211+3 EX animation and just go into njp as soon as their animations finish. You'll always get the perfect step as long as your execution is on point. 
Edit: oh yeah, db2 is only a mid for some reason...
