I don't know how efficient this combo is, but I like it:

Captain Marvel:

Ji-3 ' DB1 EX ' 22 xx DBF1 (36% Damage)

Black Adam meterless midscreen:

Ji2, b2 xx Orbs, 22b1, j2 far boot, b23 1+3 48%

Ji2, 22 xx orbs, 22b1, dash, 11 xx black magic, b23 1+3
43%

One bar

Ji2, b2 xx orbs, 22 xx MB lightning cage, b3, j3, b23 1+3 56%

Ji2, b23, 112 xx MB black magic, dash, orbs, b23 1+3 44%

Black Adam meterless corner:

JI2, b2 xx orbs, 22b1, j3 close boot stomp, 22b1 black magic, b23 u1+3 54%

JI3 close boot stomp, 22b1 orbs, b23 u1+3 48%

Compilation of Shazam combos I did yesterday, trait damage in parentheses:

Midscreen:

D2 J2 1 xx AC MB 12 xx HM MB J3 HM = 34% [46%]
AAD2 J3 1 xx AC MB 12 xx HM MB J3 HM = 36% [51%]
AAJ2 J2 1 xx AC MB 12 xx HM MB J3 HM = 46% [57%]
F223 1 xx AC MB 12 xx HM MB J3 HM = 43% [59%]
F3 J3 1 xx AC MB 12 xx HM MB J3 HM = 47% [63%]
J3 3 xx HM MB B3 J3 2 xx AC MB 12 xx HM = 53% [66%]

Corner:

112 J2 1 xx AC MB 12 xx HM MB J3 HM = 43% [63%]
F223 112 3 xx AC MB 12 xx HM MB J3 HM = 45% [63%]
J3 3 xx AC MB 12 xx HM MB J3 HM = 51% [64%]

Stage bounce:

D2 J2 1 bounce B3 J3 2 xx AC MB 12 xx HM MB J3 HM = 38% [51%]
HM MB bounce B3 J3 2 xx AC MB 12 xx HM = 43% [52%]
1 bounce B3 J3 J2 1 xx AC MB 12 xx HM MB J3 HM = 48% [61%]
F3 J3 1 bounce J2 1 xx AC MB 12 xx HM MB J3 HM = 50% (52% if you use J3 instead of J2 but it's too difficult) [66%]
J3 1 bounce B3 J3 2 xx AC MB 12 xx HM MB J3 HM = 54% [71%]

FOS Lab:

Ship trait 1 bounce B3 J3 2 xx AC MB 12 xx HM MB J3 HM = 65%
J3 3 teleporter trait J3 112 112 xx AC MB 12 HM MB B3 HM = 58%


Metropolis Street:

J3 3 xx AC MB 12 xx HM MB J3 bullets B3 HM = 59% [73%]

Here's a couple Scorpion ones

b12, teleport punch, 113, meter burn spear, b3, j3, air throw - 28%

You can add 114 to the start of that for some more damage, too. Think it's about 35%

b2, dash, 112, teleport punch, 2u3, meter burn spear, b3, j3, air throw - 33%

Bear in mind these are pseudo-resets, and can be escaped if your opponent tends to tech-roll or use wake-up attacks (but I find most players online don't).

Ares:

Ji-2 ' 112 xx D4 ' Ji-2 ' B2-3 '''' DD2 EX ' B3 ' Ji-3 ' F2-3 xx B4 (70% Damage*)
*Switch to a Ji-2 in place of the Ji-3 for 68% Damage if your opponent is Catwoman, Harley Quinn, Killer Frost, Batgirl, or Hawkgirl.

Ji-2 ' D2 xx 4 ' Ji-2 B2-3 '''' DD2 EX ' B3 ' Ji-3 ' F2-3 xx B4 (63% Damage*)
*Switch to a Ji-2 in place of the Ji-3 for 61%% Damage if your opponent is Catwoman, Harley Quinn, Killer Frost, Batgirl, or Hawkgirl.