Simple addition.
Add up positive and negative numbers in a 5 x 5 grid and watch the tiles fall! If the sum of the numbers selected equals zero, the numbers vanish and give away points. Be careful, if the sum does not equal zero, the tiles disable and you must reactivate them! Reactivate tiles by clearing numbers around them.
Use powerups to spice up your chains or to clear disabled tiles in their path! Powerups include bombs, vertical clears, and horizontal clears. Powerups dont count towards your combos sum so use it to chain to other numbers.
The more numbers chained in one swipe, the more points awarded!