Quick psi blast arbitration needed

[Tilenas]

This one goes out to all of you rules lawyers:

under RAW, is it possible to reverse psionic blast's area of effect to have the wide end of the cone adjacent to the manifester?

I get this idea from the power's statblock which gives as the spell's AoE a "30' cone-shaped burst" and as its range also 30'. What it's lacking is a phrasing that the burst is centered on the manifester. I've looked at similar powers, and they usually say something like "originates from your hands/centered on you" either in the write-up or already in the area description.
So, would it be possible to designate a point 30' away and have the cone point towards the manifester from there?

 

[Greenfield]

Burst effects always start from a specific point and expand/extend from there. Look in the book/SRD for a description of Cone areas and it will be clear.

For any such effect, select a corner of the caster's square and expand from there. It's a 90 degree arc, starting at that vertice and expanding away from the spell caster. Cones always have a range equal to their length, so a 30 foot cone area will always have a 30 foot range, and a 60 foot cone will always have a 60 foot range.

 

[Tilenas]

Alright, the cone entry clears it up, cheers!

 

[Greenfield]

Cone, Cylinder, Line, or Sphere: Most spells that affect an area have a particular shape, such as a cone, cylinder, line, or sphere.
A cone-shaped spell shoots away from you in a quarter-circle in the direction you designate. It starts from any corner of your square and widens out as it goes. Most cones are either bursts or emanations (see above), and thus won’t go around corners.
When casting a cylinder-shaped spell, you select the spell’s point of origin. This point is the center of a horizontal circle, and the spell shoots down from the circle, filling a cylinder. A cylinder-shaped spell ignores any obstructions within its area.
A line-shaped spell shoots away from you in a line in the direction you designate. It starts from any corner of your square and extends to the limit of its range or until it strikes a barrier that blocks line of effect. A line-shaped spell affects all creatures in squares that the line passes through.
A sphere-shaped spell expands from its point of origin to fill a spherical area. Spheres may be bursts, emanations, or spreads.

Yeah, it does.