I'm not quite sure what you are asking or which "them" but generally if you are a fire wiz and fighting fire enemies use your prisms and carry an ice wand (or pierce treasure cards) in case they get a shield on before your prism.
At your level I'd have 2 meteor, 2 fire blades, 4 prisms in my deck. In MB you get two of whatever you are fighting if solo, so prism-prism-blade-hit. If they are low health you won't need the blade.
If you need more damage use a feint TC or a fire trap (after you prism that target).
