PHM Pegasus is a combination simulation and action game. You control a naval hydrofoil missile boat, and need to complete a variety of different missions. Some of the missions include destroying all enemy vessels in a given area, surveillance requiring you to identify the location of enemy ships (without sinking them!), or to escort a supply ship through hostile territory. As missions are successfully completed you earn points based on how successful the mission was, and with increasing points you can advance in rank, from deck mopper up to admiral. Your performance on one mission won't have an affect on future ones, and you can choose to play missions out of order as well. Several missions include other craft you can control to help out (both ships and helicopters). A time compression mode is included, which can be used to reduce the amount of time waiting to arrive at a destination, or even left on to make the action sequences more challenging.