Fireboy and Watergirl 4 Crystal Temple is the fourth installment in Fire and Watergirl. This is the most difficult temple to complete of all the others. This game provides the opportunity for collaborative play in a captivating two-player mode. Similar to the previous three games: Fireboy and Watergirl 1 Forest Temple, Fireboy and Watergirl 2 Light Temple, and Fireboy and Watergirl 3 Ice Temple, respectively, players must solve each level in the fastest time possible to reach the exit door and collect red, blue, and gray diamonds on the road. The support and cooperation between the two players are important factors in determining the completion of the level.
Fireboy and Watergirl 4 Crystal Temple allow characters to teleport from side to side of the board, making it harder to find a solution at any level. This is the reason why it is considered the hardest part in the Fireboy and Watergirl series.