Just to make this clear, most of the credit for this guide should go to End_of_Ends. I am simply modifying it slightly.
Have you been losing all of your fights? Never won a tournament? Well, that’s probably because you started the game off pretty badly. This guide will give you step by step instructions on how to get the best start you can get, and in time you’ll be nearly unstoppable.
Step 1) If you’ve already made an account, you’ll need to scroll down and press the “Reset my account” button. This resets everything in your Ninja Warz account, other than your allies.
Step 2) When prompted to pick a clan, choose the Lotus clan. The reason you need to do this is so you can get a starting ninja with the correct stats.
Step 3) After you’ve purchased your first ninja, take a look at your health bar. If your max health isn’t 52, restart and repeat steps 1-3 over again until you get a starting ninja with 52 health.
Step 4) On the main screen, enter the Konami Code for 1 karma and a relic (+10% attack speed). The code is as follows: Up Up Down Down Left Right Left Right B A Enter. After this, go to the Daimyo and click the claim rewards button. If he does not give you karma, (preferably at least 3), then reset your account and go back to step 1. If it feels like there’s a lot of reseting that’s because there is.
Step 5) After you receive the karma, level your ninja up as far as you can. DO NOT BUY ANOTHER NINJA!
Step 6) You will need to win your first 150 fights. This is the most important part of the process, as it will give you a large karma boost and an achievement at fifty and another achievement at 150 and small karma bonus, so reset if you don’t get it.
Step 7) Dump all of your karma in to training One Ninja to level 60. However, buy white belt ninjas whenever you have enough gold to do so, leaving them at level 1. NOTE: Before buying a second white belt ninja, make sure to complete the 1v2 and 1v3 achievements Try to keep in mind the gender, age, stats and blood related achievements when buying new ninjas, as there are achievements pertaining to those statistics.
Step 8) Join your first tournament for the weapon with the highest DPS. If you’ve completed the above steps, this will be extremely easy, and will only make future fights even easier.
Step 9) Try not to power level too quickly. Fighting people at least 3 levels below you will give you 1 experience point, but will still give you the chance at looting weapons / relics that will sell for karma. When your first ninja reaches level 60, start raising a second ninja to level 60, and just repeat this process.
Step 10) Feel free to buy up to 4 relic slots when your first ninja is nearing level 60. However, do not even think about going for the 5th and 6th slots until you reach around level 30, as this is when the more powerful relics begin to unlock in the relics shop.
Note: This is not supposed to be a guide to unlocking all the achievements, just getting a high leveled ninja.
Again, 90% of credit goes to End_of_Ends, which this guide is a slight varient of. if you want to see the original go to: http://www.kongregate.com/forums/190-ninja-warz/topics/284575-guide-to-the-perfect-start