MK2’s AI is piss easy. I use Scorpion, and follow this flowchart:
Round Start: Hold Block. They’ll either try a special, or walk in. Depending on character, it can lead to a quick Spear->Uppercut combo, or just chip a bit. Regardless, they’ll start walking in.
At JUST outside sweep range: Sweep. They’ll walk right into it, or jump back.
If they get closer, start this pattern: Jump back, walk forward a touch, jump back. The closer they are, the more they’ll be in “wait mode” before jumping forward*. with Scorpion, you can get a Death Punch, and follow it up with a teleport punch->spear->uppercut combo. Does about 60% damage. Always follow this up with a forward jump ASAP, and early kick (time the kick to land as it hits its last active frames). If done right, the AI will take it like a bitch, except for Mileena. She will roll away. Let her.
Near the corner: Move forward a bit and jump back. If they neutral jump and kick you, you were too close to the corner. Let them jump over you, and take a free uppercut with sweep followup, then jump back and let them eat deathpunch and its followup.
VS. Smoke, Jade, Noob: Same tactics as before, save for hitting Jade with a Spear. However, at 3/4 screen, you can jump in and kick for free. They will attempt to fire a projectile, but you beat them. Back up a bit, then repeat the jumpkick. Depending on position, you can take their entire bar with this tactic alone. If Jade jumps back on a sweep poke, she puts herself at the perfect distance. Rush that shit down then.
Noob LOVES to try a Spear in your face after blocking a jumpkick. Block it, then fire your own back for easy damage.
VS. Kintaro: Abuse Jump Kicks. Jump AWAY if he tries the teleport stomp, and kick him out of it. This is the one fight I haven’t figured out yet.
VS. Shao Kahn: Block at the start of the round, or you might eat fireball. Then just retreat into the corner and crouchblock. Punish ever blocked charge with an uppercut, and jump forward kick for some chip. Jump back, and as you hit the corner, kick again. He should walk right into your feet. If not, Block and wait for another shoulder charge. He’ll do one eventually. Lather, rinse, repeat.
*Wait Mode explained: This is easiest to see when against Smoke, Scorpion, Reptile and Mileena. Sometimes, you’ll see them switch to Sub-Zero’s or Kitana’s stance. This is what I refer to as Wait Mode. The next move they’ll make is to jump at you, 100% of the time. Make sure you get their timing long enough for you to land, then let them eat a punish.