Godzilla can store atomic breath power by chaining Atomic Gems. Once Atomic breath is full, you can use it on a single enemy to defeat it in a single turn. Save that attack for more powerful enemies, such as the Muto or if you become surrounded.
Blast Gems
Blast Gems are created by chaining several gems in a strand. By connecting them, they will clear the rows and columns they are associated with and make Godzilla's attacks stronger. You can pair rubble next to Blast Gems to eliminate the obstruction.
Heart Gems
Heart Gems restore energy on your health bar. When below half health, use one of your turns to chain together as many heart gems as possible.
Increasing attack strength
Increase Godzilla's attack strength by drawing a line to connect pieces along a grid. The more pieces chained together, the more powerful Godzilla's attacks will become. Gems vary in strength. Blue gems are the weakest and yellow and orange gems are stronger. Match brighter colors if possible for stronger attacks. Match eight or more tiles to unlock a special tile that can trigger a combo. Try to save as many special tiles as possible before trying combos. The more special tiles available, the more damage and more points that will result from your combos.
Stars
Collect stars to unlock new areas. Up to three stars can be earned per level, based on your score. You can replay previously completed levels to earn stars that were missed the first time through. Collect stars to also level up Godzilla's Attack, Defense and Atomic stats. Attack will increases the damage dealt to enemies. Defense protects Godzilla from attacks. Atomic allows you to start with more Atomic Breath power. Try increasing your Attack level first before Defense and Atomic. Because you can reset your stats as needed, you can re-spec for higher Attack for example, in order to complete a particularly difficult level.
Atomic Gems...