Ok there’s no thread for Jack-X combos so I guess I’ll step up and post this stuff for quick reference. If you guys have some cool combos please share guys!
*Note: I haven’t checked the damage on some these combos, will update soon
 = Damage
s. = (Far) Standing
cl. = Close Standing
c. = Crouching
j. = Directional Jump
nj. = Neutral Jump
d. = down
u = up
f. = forward
b. = backward
xx = Cancel move with
, = Link
~ = Chain
> = Target\String\Follow up
LP/LK/HK/EX etc = Light, Medium, Heavy or EX version respectively
CADC = Charge Attack Dash Cancel
(ch) = Counter Hit
(corner) = Take a guess
Rocket Uppercut - DP+P
Megaton Earthquake - RDP+P
Atomic Shoulder Tackle - HCF+K
Gigaton Punch - QCF+P
Piston Gun - mash P
 cl.HP xx LP Rocket Uppercut, c.MK xx LP Rocket Uppercut, HP Rocket Uppercut - does ridiculous damage, even more if you land a jump in or crossup also if you switch cancel you get both hits of HP Rocket Upper for even more damage!
 cl.hp, LP Rocket Uppercut, c.MK xx LP Rocket Uppercut, Super Art - dat damage!
c.LP/c.LK/cr.MP xx Megaton Earthquake - great for pressuring, easy to confirm into switch cancel for damage without much scaling.
LP Rocket Uppercut, LP Rocket Uppercut, Raw Launcher
Hitconfirm Into Launcher
st.LK ~ MP > MP - this sequence is safe on block and probably the easiest to confirm
c.LP/c.LK ~ s.MP - this is punishable up close, requires correct spacing
 s.LP, c.MK xx LP Rocket Upper, HP Rocket Upper - puts opponent in range for jumpin, if you walk forward first you can get an ambiguous cross-up.
s.LP , s.LP, c.MK xx Atomic Shoulder Tackle - less damaging but leads to meaty Atomic Shoulder Tackle setups.
cl.hp, LP Rocket Uppercut, Super Art
 cl.HP xx LP Rocket Uppercut, st.LP, cl.MP, c.MK xx HP Rocket Uppercut
 J.HK, cl.hp, LP Rocket Uppercut, c.MK, EX Gigaton Punch, Super Art - one of the most damaging combos in the game!