While the counter will only go up to 11 "hits," I have mapped out a 33 string kustom fatality with Kitana. It is mostly comprised of shifting transitions, however, its the longest fatality I have ever seen. I have tried this with other characters and for some reason, it likes Kitana the best.
FF2
DF1
DB1
DF2
DF2
DB1
DF2
DF2
DF1
DB1
DB2
DB2
DB1
DB2
DB2
DB2
DB2
DF1
DB1
DB1
DF1
DF1
DF1
DD2
BB2
FB2
BF2
UU3
UU3
UU1
BB1
BB1
and one's choice of a finisher.
- Joey

I accidentaly did a Deadly Fatality on the PS2 version(I didn't know about that Kreate-A-Fatality stuff when I played it on the PS2 and the PS2 belonged to my brother and when the Fatality timer thingy came up I pressed buttons like a moron until I did it right)

I did an Ultimate Fatality on the Xbox version(I own MKA on the Xbox). It CAN get pretty tough sometimes. With the big guys I think I did... maybe an Evil Fatality?

But that's all

11 Ultimate Fatality. (Without ripping out body parts because I want it to look realistic.)

I think the highest i've done was a 7 or 8 fatality string. I'm not very good at MK:A

i usally can do 9 but iv'e only done 10 like once or twice. i think i have to do a certain order in order to do the maximum skulls fatality.

11