This question pertains specifically to Gold Book BRP's Magic system (not Sorcery, not RQ2/3).
In the "Overcoming POW" section it says "Any time a magic spell affects a living target the caster must overcome the target's POW or power points in a resistance roll." When I read the spell descriptions, some specifically say a POW roll is required (e.g. Diminish, Change) while others do not (e.g. Blast, Fire, Frost).
Do spells like Blast, Fire, Frost, and Lightning still require a POW vs. POW roll?