The Dark Times in Sommerlund
This glowing sword is the size of a bastard sword. However, the Sommersword is wielded as if it were a short sword with respect to weight and ease of use. In other words, the weapon appears to all viewers to be a bastard sword, and deals bastard sword damage, but the wielder feels and reacts as if the weapon were a short sword. Any individual able to use either a bastard sword or a short sword with proficiency is proficient in the use of a sun Blade. Likewise, Weapon Focus and Weapon Specialization in short sword and bastard sword apply equally, but the benefits of those feats do not stack.
In normal combat, the glowing golden Blade of the weapon is equal to a +2 Holy Kagnite Bastard Sword. Against evil creatures, its enhancement bonus is +4. Against Darklords, undead creatures, and Nadhazareem, the sword deals double damage (and ×3 on a critical hit instead of the usual ×2).
The blade also gives tremendous protection against magic, granting it’s wielder SR 25 while it is drawn. Any spell countered by the SR can be, as a free action, rebounded upon it’s caster.