In Fierce Fishing and similar arcade shooter games, a cannon sits at the bottom or corner of the screen for you to control. You can rotate it to aim in any direction and fire by tapping or clicking. Each shot has a cost that depends on which cannon level you are using.
Fish of different sizes and colours swim across the screen. Small fish are easy to kill but carry low rewards; larger and rarer fish take more shots but pay out much more. Each target has a set HP — the fish does not die until that HP reaches zero.
The highlight of the game is the boss targets. These are much larger than regular fish, and defeating them pays out big rewards. Boss targets tend to appear at intervals and remain on screen for a limited time — so fast decisions matter.
Some games also include special weapons or skills — such as an electric attack that damages several fish at once, or a blast that wipes out all nearby fish. Using these special skills at the right moment is the approach experienced players take.