If you want the badges easy and painless join servers randomly until you see that the world is in 'Havoc' (Happens after an alliance wins) You will have unlimited cash.
Not to new players- If you dont follow the tutorial exactly your pretty much screwed. Your either stuck waiting an ungodly amount of time waiting to regain resources to complete the next part or you have to skip the tutorial all together. Very very annoying.
The stars in the bottom double up your score. If you have 4+ moves left you will get +30 XP. If you have 11+ moves left you will get 33+[3X(Moves above 11)]. Go for multi heros early on and do the cheap upgrades. Buy the perk that lest your heros regain 50HP every move and then the Chakura one. Keep in mind that the more you kill the less you have to fight when fighting the boss. On the main map avoid the spots that give enemies faster attack until later on.