AOE Spells - 1 attack roll vs. All Targets?

[BASHMAN]

A party of PCs? Roll once, since they all have different saves.

A natural 20? The person closest to the point of origin takes the crit, everyone else takes normal damage.

 

[Elder-Basilisk]

I'm in the category of: there's no good way to do it. It's a bad idea and don't try.

However, if you insist on trying, here is a side effect to consider. Most any "one roll for everyone" mechanic ends up punishing low defense characters relative to the rest of the party. You will never have a situation where the guy with the 22 reflex defense gets hit but the guy with the 16 reflex defense is missed. There will be lots of times where the 16 is hit but not the 22 but never the other way around. Now that's not game changing in the way that "I rolled a 20, I crit you all!" is. Nor is it game changing in the way that "my thunderburst hits defense 33; you all take 15 points of thunder damage and are stunned, save ends." But I'm pretty sure it would be frustrating to be the guy who is always hit.

 

[PHGraves]

From the DDE Quickstart

If you make an attack against multiple targets, you
don’t roll damage for each target – just roll that once. It’s best when you attack multiple targets to roll damage first, and then roll your attacks.

 

[Plane Sailing]

If you are looking for house rules, here's one that came to me.

Every AoE spell has a center right? So you could do it like this:

Target a square.
You get a +2 bonus on the enemy in the target square.
For every square the effect extends out, subtract 1 from the result of the casting roll.
...

I rather like this idea in principle (although I'd not use a +2 bonus, and just take -1 (or -2) for each square away from the main target square). As others have said, it is difficult to decide what would be the best approach without seeing the rules yet, but this would certainly be an interesting idea in principle to test out.

Cheers

 

[hamishspence]

rolling damge first

Has one advantage: it gives the feel that its all one explosion hittting with equal power. the players may have different amounts of skill or toughness or knack for dodging, to mitigate this hit, but its still one single explosion, or whatever spell it is.