So, does this make sense?
<config> <append xpath="/entity_classes/entity_class[@name='playerMale']"> <effect_group> <effect_group name="ArmDismemberModifier"> <requirement name="HitLocation" body_parts="arm"/> <requirement name="EntityTagCompare" target="other" tags="zombie"/> <passive_effect name="DismemberChance" operation="perc_add" value="0.5"/><!--Arm Dismemberment Multiplier Value--> </effect_group> </append> <insertAfter xpath="/entity_classes/entity_class[@name='playerMale']/effect_group/passive_effect[@name='ArmDismemberModifier']"> <passive_effect name="DismemberChance" operation="base_set" value="0.1"/> </insertAfter> </config>