Cover

Cover allows creature in LOR to avoid damage more easily. There are three types of cover which provide the following benefits

Against melee hit rolls, however, you reduce the penalty by half(round down).

Cover is relative to a target and is just generally directional. You main gain cover from one creature and not gain cover to another.

Light Cover 

-1 to incoming hit roll

Standard Cover

-2 to hit roll against you and +2 to reflex slaves

Heavy Cover

 -4 to hit roll against you and +4 to reflex slaves

High Ground

High Ground is considered as standard cover and when on hign ground, attacks decrease cover by 2 degree and gain advantage on prone targets 

In addition creatures on high ground gain 2 degree of cover higher than their current cover against attacks from creatures on lower ground