Variable level spell

[Phosphate]

Here's a spell that can be cast at a spell level chosen by the caster.

To clear up any misunderstanding about spells known: all sorcerers know this spell by level 1 (WITHOUT it counting towards spells known), and wizards can prepare it from memory.

Arcane Blast
Evocation

Level: See Text
Components: S
Casting Time: 1 standard action
Range: See Text
Effect: A blue ball of radiant arcane energy
Duration: instant
Saving Throw: See Text
Spell Resistance: Yes

This spell can be prepared in a slot of any level or spontaneously cast using a slot of any level. You throw a ball of pure arcane power towards an opponent, making a ranged touch attack. If you succeed, you deal dx*class level/2 (limited to 5dx for levels 1-3, 8dx for levels 4-6 and unlimited for the rest) damage. The dice used depends on the level of this spell: it is d4 for 1-2, d6 for 3-4, d8 for 5-6, d10 for 7-8 and d12 for 9+.

The type of damage also depends on spell level: at level 1-3 it deals electric damage, at level 4-6 you can choose between electric and fire damage, at level 7-8 you can choose any type of energy damage and at level 9 you can choose any type of energy damage or you can choose to deal untyped damage.

As for range: it is Close for levels 1-2, Medium for 3-5, Large for 6-8 and line of sight for level 9.

As an additional effect, beyond level 5 the spell will also engulf everyone in a 5 feet*spell level spread around the target, dealing half the damage sustained by the target. This effect can be avoided entirely by passing a Ref save.

This spell cannot be modified with metamagic, nor can it be counterspelled.

[TuggyNE]

This honestly seems like more of a psionic bent than arcane casting. (Although the change in die-size isn't very psionic.)

Alternatively, this could be a class feature that upgrades an SLA... as written, it's a class feature masquerading as a spell (even more so than most spells). (Giving sorcerers effectively 9 free spells known? Really?)

Essentially it's just got crazy scaling: higher levels give additional range, more additional range*, additional damage, more additional damage*, better damage types, and finally more targets. Compare that to a conventional spell that gives additional range and additional damage (capped, usually). You have to learn other spells in order to get better damage types or more targets.

*They not only expand numbers but also measurement types/ranges.

[W3bDragon]

Since this is an "Arcane" blast and not an "Elemental" blast, I'd say drop all the elemental types of damage and make it plain force damage across all levels. That's makes more sense from a thematic aspect. Of course damage should be reduced accordingly, since force damage is very hard to resist. I'd say stick with d4s. Also, I agree with no metamagic on it, but perhaps counterspell possible with another arcane blast? Makes for awesome imagery.

1st level: 1d4 per level. Cap at 5d4.
2nd level: 1d4 per level. Cap at 7d4.
3rd level: 1d4 per level. Cap at 9d4. Splash half damage in 5 ft radius.
4th level: 1d4 per level. Cap at 11d4.
5th level: 1d4 per level. Cap at 13d4. Increase Range to medium.
6th level: 1d4 per level. Cap at 15d4.
7th level: 1d4 per level. Cap at 17d4. Increase splash area to 15 ft radius
8th level: 1d4 per level. Uncapped. Increase Range to Long.
9th level: 1d4 per level. Uncapped. Increase splash area to 30 ft radius. Increase range to line of sight.

Maybe something like this?