AoE Spells vs Creatures Larger Than Medium

[Olaf the Stout]

In our last session we had a Fireball cast that partially hit the Enlarged Hexblade (2 of his 4 squares were in the 20ft radius of the spell).

In that situation do you roll a dice to see if the person is hit? (50/50 chance in this case, but could be more or less in other situations, especially if the creature was Huge) - This was the option I used during the session. I rolled a 3 on a d6 and decided that the Hexblade was just missed by the edge of the Fireball.

Or if just one square of their base is in the area of effect are they counted as being affected by the spell?

Or do all of their squares need to be in the area of effect in order for them to be affected by the spell? (I doubt it, but you never know).

Olaf the Stout

 

[StreamOfTheSky]

If any square of the creature is in the area, they take full damage.

 

[Abciximab]

If any square of the creature is in the area, they take full damage.

Ditto. If you occupy any space within the area of effect you suffer the full effect.

From SRD : When determining whether a given creature is within the area of a spell, count out the distance from the point of origin in squares just as you do when moving a character or when determining the range for a ranged attack. The only difference is that instead of counting from the center of one square to the center of the next, you count from intersection to intersection.

You can count diagonally across a square, but remember that every second diagonal counts as 2 squares of distance. If the far edge of a square is within the spell’s area, anything within that square is within the spell’s area. If the spell’s area only touches the near edge of a square, however, anything within that square is unaffected by the spell.

 

[irdeggman]

See page 148 of the PHB for examples of taking up multple squares - specifically for difficult terrain, but the same thing applies to area effects.
"If you occupy swuares with different terrain, you can o=move only as fast as the most difficult terrain you occupy will allow. (this is often significant for creatues whose space fills more than one square, such as a giant)."

From the SRD (or pg 175 of the PHB)

When determining whether a given creature is within the area of a spell, count out the distance from the point of origin in squares just as you do when moving a character or when determining the range for a ranged attack. The only difference is that instead of counting from the center of one square to the center of the next, you count from intersection to intersection.
You can count diagonally across a square, but remember that every second diagonal counts as 2 squares of distance. If the far edge of a square is within the spell’s area, anything within that square is within the spell’s area. If the spell’s area only touches the near edge of a square, however, anything within that square is unaffected by the spell.

 

[Herzog]

I seem to remember a (house?) rule that said you would effectively get a similar benefit as if you had the Improved Evasion feature when half or less of your space was within the spell's area:

no damage when you make your save. (can't remember if you got full or half damage on a failed save)

 

[Starbuck_II]

I seem to remember a (house?) rule that said you would effectively get a similar benefit as if you had the Improved Evasion feature when half or less of your space was within the spell's area:

no damage when you make your save. (can't remember if you got full or half damage on a failed save)

Definate houserule.

 

[irdeggman]

Definate houserule.

Could have been a throw back to 2nd ed when area effect spells were calculated by drawing circles from the center of a square and not from the corners and it didn't have the specific rule about edges of the squares.