Here are my tips on:
How to score high in Bejeweled BlitzMove fast, and I mean FAST.
Bejeweled Blitz rewards speed. Don't sit and wait for everything to cascade down the screen. There is no time for marvelling at your work. Once you make a move, immediately make the next move. Remember, the faster you make a move, the sooner you can get into the speed bonus.
Everybody loves explosions.
Just like every natural born man, Bejeweled Blitz loves explosions. While you are cranking through the game do not miss opportunities to match fours and fives. Matching fives creates the awesome power of destroying all of one color. Power cubes are the main drivers of multipliers.
You must match multipliers.
No single tip is more important for high scores than multiplier cubes. If you want to hit a high score, you must have at least a four times multiplier. Multiplier cubes are created when you score big on one move - see item number two.
Use a hint.
Bejeweled Blitz has a hint button for a reason. Use it. Sometimes you just need to get out a quick rut so you can get your rhythm back into the game. As far as we can tell there is no penalty for using the hint button (aside from taking time to actually use it.)
Don't like the look of the game? Restart.
With one minute of play constantly tantalizing you to play one more game Bejeweled Blitz is a deceptive time sink. If you want to hit the high scores you need to stay focused on the games you can score the highest in. If you load a game and the jewels didn't fall right or you're ten seconds in and still have a low score, reset the game.
You can reset by hitting menu >> main menu >> yes >> play
These are my tips if you have any others please feel free to post them in the comments!
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