When fighting Scorpion at the end of the game, continually strafe around him to dodge his specials, then attack when he has finished an attack of his own and is vulnerable. Also, try to save your Breakers, but use them when necessary.
The following trick is a very easy way to defeat the CPU, especially Scorpion for Shujinko's Spear move. Confront Scorpion and exit until you can fight him as Baraka. Do the "Mutant Blades" move and the "Chop Chop Blades" move every time he gets back up. You may need to switch up the rotation of the two specials, but the "Mutant Blades" move (Forward, Forward, A) works most of the time when he is just getting back up. When you think he is going to attack at close range, then use the "Chop Chop Blades" move (Down, Up, A). Save the game, go to the difficulty option, and set it on the easiest. This works because he is constantly healingm and if he hits you, he takes 300% damage.