THE KING OF FIGHTERS XV

Not so much a guide but here is the best way to get to this rank as quickly as possible.
When you first start Ranked and it asks you to play 3 matches to determine your rank DECLINE IT

The Exact Message you get is :

In order to assign an initial rank , you battle three CPU opponents in tutorial battle. Your Rank depends on your results :
Choose : SKIP

If you skip the tutorial, you will automatically be placed in a higher rank. Do you want to proceed?
Note : this is not recommended for beginners
Choose : Yes

Welcome to Rank 15

On 2 different gamertags I fought the matches and both times ended up being Rank 13.

If you decline you start straight away at Rank 15 , meaning you only have to rank up once to get both achievements for Ranking up and reaching Rank 16 (Master Achievement) - You need 7 wins in a row for this.

You only get the ranking up Achievement when you rank up to Rank 16 as well. I ranked up all the way from Rank 13 and it only unlocked at Rank 16.

To Rank up you need to win 3 out of 5 fights when moving from 15 to 16 , 20 to 21 and 30 to 31 which is where you unlock the Champion Rank and associated Title.

I used a boosting method for my wins :

1. If you have 2 Xbox's change your regional settings to a country which isnt common like New Zealand or South Africa.
2. In the options change the settings to :

Opponent Strength : Any Rank
Connection speed : Lvl 5 Only - Only if on same network otherwise change to Any
Region : Same Region. ( Use South Africa or New Zealand )

3. Both Search at the same time.

I did 101 Victories without anyone else joining , but this was before the game launched worldwide. I can now confirm though that using the same region works as a boosting method. I have boosted two of my friends to Rank 16 with no issues.

I hope this works and I save you a good few matches. By starting at 15 insted of 13 it could save you easily over 15 matches, then you can relax and get your 30 wins without worrying about having to get back to Rank 16.