Best tips I can give as someone who is 400k+ power on server 289 and who has been playing for 3 years.

1. Keep your account-level low. If you max you level out too quickly you will be put into Events with "whales". It will ruin your fun.

2. Prioritize power over ninjas. Ninjas will come and go as meta changes. Power stays forever.

3 Focus on Position 1 ninja; since 1.0 it's always been this way. Initiative rules the game.

4., In order this is what I would focus on; Training Pots (ninja assist), runes, refines, charms, battle armor, magatamas

5. But don't slack on the others either.

Ex. Position 1 has level 6 charms and refines, P2-4 should be no less than level 4 charms and refines.

6. If you do plan on spending, spend wisely.

7. Buy only power*

8. If you do want to buy ninjas, Look for meta ninjas that would be compatible with ninjas you have already. No need to buy a full team right off the bat.

9. The only time you should upgrade is during rebate events.

10. Understand why certain ninjas/teams are meta to be able to find counters and to be able to maximize the ninjas you have