You can modify an energy-based spell to use another type
of energy instead.
Prerequisites: Knowledge (arcana) 5 ranks, any metamagic
feat.
Benefi t: Choose one type of energy (acid, cold, electricity,
or fi re). You can then modify any spell with an energy
descriptor to use the chosen type of energy instead. An energy
substituted spell uses a spell slot of the spell’s normal
level. The spell’s descriptor changes to the new energy
type—for example, a fi reball composed of cold energy
is an evocation [cold] spell.
Special: You can gain this feat multiple
times, choosing a different type of energy
each time.
以上原文
大致意见如下
1、对于法术本身没有描述符的，可以改，但是不获得描述词
2、对于法术本身有描述词的，改变能量类型后将改变描述词
3、法术造成的异常状态维持不变，除了像强酸箭那种带后续效应的
PS：法术什么的不带出处不带原文会查死人的
