Point of Origin for an Emination [Archive] - Wizards Community

Point of Origin for an Emination [Archive] - Wizards Community

Post/Author/DateTime Post
Level2Intern
12-03-07, 10:32 PM We had an issue come up in game recently regarding the point of origin and an emanation effect... in fact it was everyone’s favorite emanation Antimagic Field cast by a gargantuan dragon... boo!

AMF is a 10' radius emanation centered on the caster. I am under the impression that an emanation has a point of origin at the center of the casters square if the range is personal otherwise the emanation has a point of origin at a grid intersection.

This would have been simple enough had the caster been medium sized; however the gargantuan dragon complicates the matter.

We discussed three possible variations:

1. The AMF's point of origin is centered on the dragons square and completely enclosed within his 20' space since the AMF has a 10' radius.

2. The AMF's point of origin is a grid intersection somewhere within the dragons space (his choice). The result is that he is partially affected by the AMF and some of the area of effect lies outside his space.

3. The AMF's point of origin is each and every grid intersection within the dragon’s space, effectively creating a 10' area of antimagic from the boundaries of his space.

Am I missing a description somewhere that details the point of origin for emanations? Any advice would be much appreciated. Thanks!
rimble
12-04-07, 03:12 PM Area: 10-ft.-radius emanation, centered on you

<<snip>>

Should a creature be larger than the area enclosed by the barrier, any part of it that lies outside the barrier is unaffected by the field.

Seems like #1 to me. I'd interpret 'centered on you' to mean the center of your physical being...so it'd actually be centered a bit off the ground in the dragons tummy or whatever...I'm sure there are bizarre creatures with difficult to determine 'centers'...pick a reasonable spot and go with it.
mvincent
12-04-07, 03:27 PM The AMF's point of origin is a grid intersection at the center of the dragon's area. It would be completely enclosed within his 20' space since the AMF has a 10' radius.

It's been discussed here (http://forums.gleemax.com/showthread.php?p=13342907) and here (http://www.enworld.org/showthread.php?t=193314), and WotC customer service has said:
"the caster is affected by the field.

the center of the emanation is the caster.

The Area of the spell does not change with the size of the caster, the dragon would not be completely encompassed by it."

House-ruling otherwise is not unreasonable though.
rimble
12-04-07, 05:39 PM Wow, that's messy. How do people keep track of moving emanations like that? I've always let it emanate in all directions, basically affecting nine more squares than it should, not sure how to cleanly keep track of it otherwise.

Would you let the PC pick a corner and let them keep track of it? Can the PC change the corner it's emanating from on his action?

Do you just set a pre-specified corner for such affects? Like it always emanates from the side closest to the DM, left corner?
Level2Intern
12-04-07, 07:57 PM Mvincent: You rock!

Thanks, that is perfect :D
mvincent
12-04-07, 08:15 PM Wow, that's messy.Yup, especially since medium creature at the center of a 10' emanation will always have a single (diagonally) adjacent square that is not covered by the emanation. I gotta think the designers didn't actually play this way.

How do people keep track of moving emanations like that?A steel sqwire template would be the easiest way.

I've always let it emanate in all directions, basically affecting nine more squares than it should, not sure how to cleanly keep track of it otherwise.I have a feeling that this is how most players handle emanations that are centered on a creature.

Would you let the PC pick a corner and let them keep track of it? Can the PC change the corner it's emanating from on his action?Yes to both.

Post/Author/DateTime	Post
Level2Intern 12-03-07, 10:32 PM	We had an issue come up in game recently regarding the point of origin and an emanation effect... in fact it was everyone’s favorite emanation Antimagic Field cast by a gargantuan dragon... boo! AMF is a 10' radius emanation centered on the caster. I am under the impression that an emanation has a point of origin at the center of the casters square if the range is personal otherwise the emanation has a point of origin at a grid intersection. This would have been simple enough had the caster been medium sized; however the gargantuan dragon complicates the matter. We discussed three possible variations: 1. The AMF's point of origin is centered on the dragons square and completely enclosed within his 20' space since the AMF has a 10' radius. 2. The AMF's point of origin is a grid intersection somewhere within the dragons space (his choice). The result is that he is partially affected by the AMF and some of the area of effect lies outside his space. 3. The AMF's point of origin is each and every grid intersection within the dragon’s space, effectively creating a 10' area of antimagic from the boundaries of his space. Am I missing a description somewhere that details the point of origin for emanations? Any advice would be much appreciated. Thanks!
rimble 12-04-07, 03:12 PM	Area: 10-ft.-radius emanation, centered on you <<snip>> Should a creature be larger than the area enclosed by the barrier, any part of it that lies outside the barrier is unaffected by the field. Seems like #1 to me. I'd interpret 'centered on you' to mean the center of your physical being...so it'd actually be centered a bit off the ground in the dragons tummy or whatever...I'm sure there are bizarre creatures with difficult to determine 'centers'...pick a reasonable spot and go with it.
mvincent 12-04-07, 03:27 PM	The AMF's point of origin is a grid intersection at the center of the dragon's area. It would be completely enclosed within his 20' space since the AMF has a 10' radius. It's been discussed here (http://forums.gleemax.com/showthread.php?p=13342907) and here (http://www.enworld.org/showthread.php?t=193314), and WotC customer service has said: "the caster is affected by the field. the center of the emanation is the caster. The Area of the spell does not change with the size of the caster, the dragon would not be completely encompassed by it." House-ruling otherwise is not unreasonable though.
rimble 12-04-07, 05:39 PM	Wow, that's messy. How do people keep track of moving emanations like that? I've always let it emanate in all directions, basically affecting nine more squares than it should, not sure how to cleanly keep track of it otherwise. Would you let the PC pick a corner and let them keep track of it? Can the PC change the corner it's emanating from on his action? Do you just set a pre-specified corner for such affects? Like it always emanates from the side closest to the DM, left corner?
Level2Intern 12-04-07, 07:57 PM	Mvincent: You rock! Thanks, that is perfect :D
mvincent 12-04-07, 08:15 PM	Wow, that's messy.Yup, especially since medium creature at the center of a 10' emanation will always have a single (diagonally) adjacent square that is not covered by the emanation. I gotta think the designers didn't actually play this way. How do people keep track of moving emanations like that?A steel sqwire template would be the easiest way. I've always let it emanate in all directions, basically affecting nine more squares than it should, not sure how to cleanly keep track of it otherwise.I have a feeling that this is how most players handle emanations that are centered on a creature. Would you let the PC pick a corner and let them keep track of it? Can the PC change the corner it's emanating from on his action?Yes to both.