A shield system is a protective energy barrier that a starship (or other object) generates around itself to defend against harm. Shield systems are quite common, especially on military starships such as Star Army Starship Classes.
In the Star Army Role-Play, there are three types of shield systems - Electromagnetics, gravitational and spacial distortion. Each has its own advantages and disadvantages.
Modifiers affect each point inflicted against and are not respective of the full capacity of a shield.
Electromagnetic shields create a strong field that repels incoming weapons fire. Magnetic shields being active could cause some problems related to sensors in regard to initiating MagRes scans as well as to be easily found out by the same. They are, however, terrific at deflecting incoming beams attack, holding some effectiveness also against projected particle weapons. They are very bad at defending against kinetic forces.
Gravity-based shielding creates an artificial gravity field to move incoming weapons fire off-course. Most effective against projectile weapons. Gravitons emitted from a ship can totally block the effect of graviton beams, but in a similar fashion also may cause an effect that will greatly hinder the ship from using FTL engines when they are active - they also show up pretty well on graviton sensors. The highlight, of course, is that they afford the defending ship superior resistance to kinetic impacts, but beams slice in very easily.
Distortion shields work by bending the space around an object so that incoming weapons fire is steered around the ship. This is the most energy-consuming type of shield. In terms of performance, it is a compromise between gravitational and electromagnetic barrier systems but costs more to build, maintain with a lower overall defensive capacity and is best used on a starship.
Perhaps some weapons are able to completely pierce barriers? Or perhaps the addition of a penetration stat, which is inversely proportional to the range and usually demands a weapon be made much larger and rugged than it would otherwise be.