Random Magic Weapons (any level)

A flaming burst weapon functions as a flaming weapon that also explodes with flame upon striking a successful critical hit. The fire does not harm the hands that hold the weapon. Flaming burst weapons deal +1d10 points of bonus fire damage on a successful critical hit. If the weapon's critical multiplier is x3, add +2d10 points of bonus fire damage instead, and if the multiplier is x4, add +3d10 points of bonus fire damage. Bows, crossbows, and slings so enchanted bestow the fire energy upon their ammunition.
Aura: Strong evocation
Caster Level: 12th
Requirements: Craft Magic Arms and Armor and flame blade, flame strike, or fireball
Price: +2 bonus
Source: Dungeon Master's Guide v.3.5