Earthquake players match sets of creature cards from their hands with cards already in play and score points by multiplying the number of cards in the set played by the total number of cards from that suit on the table. The winner is the first player to earn 100 points (or more if a longer game is desired). Game mechanics are so simple that the game barely has any mechanics at all, desirable in that this makes Earthquake fast to learn and play and allows players to concentrate on strategy rather than rules.

Players' strategies can be shaken up by the card that is this game's namesake: when the "Earthquake" card is played, all cards on the table are discarded, and any plans players have to score points off the cards on the table are shattered. Other special cards include "Prosper" (which grants points), "Time Warp" (which allows unlimited card plays for one turn), and "Opportunity" (which allows a player to draw extra cards).

Each deck contains a rules pamphlet and 70 cards, 60 divided into five equal color-coded suits, two "Clones" (wild cards), and 8 special cards. Art on the cards is humorous and all the cards in each suit are done by the same artist, so there is a certain homogeneity amongst them (green elves by Jeff Miracola, black skeletons by Christopher Rush, blue wizards by DiTerlizzi, white soldiers by Liam Sharp, and red goblins by Scott M. Fisher). There are also several female cards (although the skeleton is only distinguishable as such by her purple ponytail and garb, and gender for a few of the elves is uncertain).

Earthquake is intended for two or four players (although two decks could easily be combined to accommodate a larger group) and play time is about 20 minutes per game. This game is ideal for children, not just because it is easy to learn and play and because the pictures are entertaining, but also because it allows them to practice rudimentary math skills and because it can be played through quickly.

Earthquake earns a full 6 pips on a 6-point scale.