THE best matchup in MK2. scorpangel and I once did 160 Kitana vs Jax matches lol.
This was the video that put me on the map:
A certain someone in the vid claimed Jax should never lose to Kitana, and that he would 20-0 my Kitana. I accepted his challenge, and we agreed to record. Haven't heard much from him since....
KITANA
Most important rule- never stop chasing after Jax. A lot of mediocre Kitanas attempt the "hop backwards and throw air fans over and over" strategy. I myself used to do this when I was new to PS3. This is exactly what Jax wants to see you do, as you aren't in his zone when you do that. Instead, you need to always be in Jax's box. Kitana has a fast walk speed, so she can just chase him down until she gets him in a corner. Who cares if you take damage from a ground pound, you need to be up close to him to win. Pressure him with sweeps, IAFs, fan swipes, punches, crouch punches, low toes.... everything she's got in her arsenal. Test the Jax you're playing against- if he is really good at anti-airing, then be very conservative with your jumps. But if the Jax player can't aaHK you out of jumps, go for it all day long. Jump punch is harder to anti-air, but doesn't combo with air fan like a jump kick does. If you jump kick him as he ground pounds, you can add on an air fan and another JK or HK for 50% damage. Square wave only gets you in trouble in this match. Fan raise is awesome, especially in the corner, but make sure you don't use it up close where Jax can block it, or he can do a massive hammer punch combo.
JAX
Of course you don't want Kitana anywhere near you. Anti-air HK all her jump-ins. You can also uppercut or crouch kick her out of jump ins. Use crouch punches to keep her away, and do a ground pound immediately afterwards. Limit your jumping, as you don't want to chance landing in a fan raise. Multi-ground pounds are risky against Kitana, as it gives her an opening to JK/fan/JK. Use wave punches to keep her off balance. If you get good at golden punching, you can make Jax into a tank. If you're playing a Kitana that won't stop chasing you down, give her a taste of her own medicine and go for a multi-slam throw. That alone takes off I believe 45%. Backbreak her when she's in close and you anticipate her jumping or crossover kicking. Gotcha grab is fairly useless- she usually gets a free hit in after he does it. You don't want to end up in a corner vs Kitana's jab, but chances are she'll chase you into one. Be very careful with your ground pounds in the corner, as it's even easier to be JK/fan/HK'd here. Basically, keep your distance from her and win.
I really don't know overall what it is. Jax is stronger, but Kitana's fast sweeps and big combos can really hurt him.
I think it's a 6-4 match for Jax, but if Kitana plays out of her mind, watch out.
