Homebrewed spells for Dungeons and Dragons 3.5 edition!

[Droid Tony]

Power Word: Burn
Evocation( Fire )

This is very weak for a 7th level spell. And just about all the Power Word spells are enchantments. Still a foe at this level will just laugh at 100, or more likely 50 points of damage. Or just be immune to fire.

Acid Storm is a level lower, hits all in 20x 20 and does 15d8 damage, for example.

You might want to add a limit to the size of an object to be effected also.

Dragon Breath

Your close to the official spell, but it has more damage types, plus slow and sleep and such....and does 10d8(1d8/2 levels) damage.

Threshold.

Abjuration.
Sor/Wiz 6, Cleric 6..

Looks ok

[Droid Tony]

Wait, sorry: There is a Dragon Breath official spell?

Yes, in the Spell Compendium. You can also find the Refusal spell there that is similar to Threshold.

[Coins]

I have a list of roughly 50 homebrew spells. Will update when I can post link.