School transmutation [fire]; Level bloodrager 3, magus 3, sorcerer/wizard 3; Elemental School fire 3
CASTING
Casting Time 1 standard action
Components V, S, M (a drop of oil and a small piece of flint)
EFFECT
Range close (25 ft. + 5 ft./2 levels)
Target fifty projectiles, all of which must be together at the time of casting
Duration 10 min./level
Saving Throw none; Spell Resistance no
DESCRIPTION
This spell allows you to turn ammunition (such as arrows, crossbow bolts, shuriken, and sling stones) into fiery projectiles. Each piece of ammunition deals an extra 1d6 points of fire damage to any target it hits. A flaming projectile can easily ignite a flammable object or structure, but it won’t ignite a creature it strikes.
Do bonus dice from Channel Smite or spells such as elemental touch or flame arrow multiply on a critical hit?
No. See Multiplying Damage: “Exception: Extra damage dice over and above a weapon’s normal damage are never multiplied.” The general rule is the only dice you multiply on a critical hit are the actual dice from the basic weapon (d8 for a longsword, 2d6 for a greatsword, and so on).
[Source]
By the way…
This spell can start fires on a ship.
