KarinsDad said:Note: I know how WotC customer service will answer this and I understand the intent, but so far, nobody has posted actual rules to deny it. It's all been opinion and narrow interpretation.
...blast 3, which means the power affects a 3-square by 3-square area adjacent to you.
Lucas Blackstone said:Since people are twisting the intent of the blast shape, I suppose twisting has to be done a bit more to get them to see the light.
The following is the definition of side.
Side - one of the surfaces forming the outside of or bounding a thing, or one of the lines bounding a geometric figure.
This is the blast area of a power as defined by the PHB.
Blast: A blast fills an area adjacent to you that is a
specified number of squares on a side. For example,
the wizard power thunderwave is a blast 3, which
means the power affects a 3-square-by-3-square area
adjacent to you. The blast must be adjacent to its origin
square, which is a square in your space. The origin
square is not affected by the blast. A blast affects a
target only if the target is in the blast’s area and if there
is line of effect from the origin square to the target.
So since you can CLEARLY see one of the sides of is well over the 3 squares ( in this case) limit, it does not meet the parameters.

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Rulebook featuring "high magic" options, including a host of new spells.