There are several elemental attacks from weapons you can exploit against enemies. Each race has different vulnerabilities you can view when you play them in the campaign. Ice attacks fair well against unarmored enemies (orcs, humans) and will freeze them into immobility. Lightning attacks do well against metal clad enemies and spearmen or axemen. Poison attacks fair well against Elves (or Vells) and do stack damage. Curse attacks reduce the defence and offence of the enemy to near zero, but do no damage. Fire attacks are the best to use in general, since burning enemies cannot attack, and the fire damage can be stacked. When playing Gerald, Lucretia, or Kendal, try to buy an elemental weapon at the first opportunity. Regnier will not be able to buy any elemental weapons since he can imbue his weapon with fire by expending some SP (hold the B button in battle to toggle this power).