Crystal storm

The value of the gems sacrificed to the spell will cause different effects

Gems worth 100gp cause the spell to deal 1d8 piercing damage to the target of the spell 

Gems worth 500gp cause the spell to split into two beams allowing the caster to hit 2 targets for 1d8 piercing damage 

Gems worth 1,000gp cause the affect of 500, but increase the damage to 2d8 piercing damage

Gems worth 2,500gp cause the spell to split into 3 beams that deal 2d8 piercing damage 

Gems worth 5,000gp cause the affect of 2,500, but increase the damage to 3d8 piercing damage