Spells may be cast during combat, though global spells are disabled. Combat spells may target a unit or a group of units of the enemy collectively, damaging or temporarily handicapping them. Handicaps are usually introduced alongside direct damage, and vary from short-term paralysis to poisoning or a curse. Most spells have a maximum range. All ranged attacks (including some types of spells), and some melee strikes can result in friendly fire. For example, an archer firing an arrow at a target can hit and injure a friendly unit if it is on the line of fire. Trees, buildings and other obstacles scattered around combat maps also hamper ranged attacks as well as movement to various degrees, and can be used to one's advantage to great effect.