There are a lot more alternate costumes in Mortal Kombat for the PS Vita than in the version for PS3 and Xbox 360.
Here is the list I’ve found so far. If you find more, please leave comments and I’ll add them.
Ermac Mortal Kombat 2 – Complete Bonus Challenge Tower Mission 115
Ermac Mortal Kombat 3 – Complete Bonus Challenge Tower Mission 95
Kenshi Altternate – Complete Bonus Challenge Tower Mission 150
Mileena Mortal Kombat 2 – Complete Bonus Challenge Tower Mission 9
Noob Saibot Mortal Kombat 3 – Complete Bonus Challenge Tower Mission 147
Rain Mortal Kombat 3 – Complete Bonus Challenge Tower Mission 150
Reptile Mortal Kombat 2 – Complete Bonus Challenge Tower Mission 103
Reptile Mortal Kombat 3 – Complete Bonus Challenge Tower Mission 61
Scorpion Mortal Kombat 2 – Complete Bonus Challenge Tower Mission 32
Scorpion Mortal Kombat 3 – Complete Bonus Challenge Tower Mission 16
Skarlet Alternate – Complete Bonus Challenge Tower Mission 150
Skarlet Mortal Kombat 2 – Complete Bonus Challenge Tower Mission 38
Skarlet Mortal Kombat 3 – Complete Bonus Challenge Tower Mission 109
Smoke Mortal Kombat 3 – Complete Bonus Challenge Tower Mission 124
Sub-Zero Mortal Kombat 2 – Complete Bonus Challenge Tower Mission 66
Sub-Zero Ultimate Mortal Kombat 3 – Complete Bonus Challenge Tower Mission 2
