Here is some Bubble Witch Saga 2 Help to fill in some blanks and let you know about some things you might not be aware of.
View more on the Bubble Witch Saga 2 Guide Wiki
Aiming – You can pull back and drag forward to aim your bubbles. They will also bounce of the walls and ceiling, but not the bottom where they will disappear without points.
3 Stars – To get 3 Stars you need to get a high enough score. The trick to getting your score up high is to spawn as many spiders as possible by making matches and triggering Hot Pots by making consecutive matches in a row. Keep in mind that if you fail to make a match all of your spiders will disappear. Hot Pots are go away after a certain amount of shots and don’t have a timer so you can relax and plan you next shot to maximize your score. It’s good to try and look ahead and save a large amount of droppable bubbles until the screen if full of bugs and flames.
Difficulty – When playing a stage over and over with it seeming like it’s impossible keep in mind this game is geared and programmed to make money so they do want you to just breeze through. Since the colors of each orb are different each time you try a particular stage the best thing you can do is take your time and keep trying. You are bound to get a good roll sometime. You should try to focus on the mission goal to win and not be to tempted to make matches all the time as you could run out of ammo before you can complete your goal.
Gold Bars – This can only be gotten be purchasing with real money though you will start with 50. Best to hold on to it until you really need it in later areas.