Targeting a Fireball behind enemies?

[T-Bone JiuJitsu]

I have looked thru the rule books and cannot find anything to help solve this question I have regarding targeting of area of effect spells like Fireball.

Could a short spellcaster (Gnome, Halfling, etc) target a fireball to go off in an area behind three rows deep of fighting humanoids? If he were firing an arrow, he would need precise shot AND the target would have cover. Yet, according to the rules as I've read them, all those fighting people in front of him don't affect his ability to pinpoint one specific spot on the grid that will provide maximum enemy exposure to the blast.

What about targeting a fireball so that allies are just outside the blast radius (I mean they are right next to a square that is fully in the blast). Is that "legal" or "Fair". Should I use the grenade-like scatter table for thrown items, or is that hindering the spellcasters abilities too much.

 

[Kalanyr]

If he has line of sight and line of effect to the square he can place it there.

As long as the player isn't taking to much time carefully lining up where to place the fireball, its probably not worth disadvantaging the spellcaster, the spells are their main weapons, grenade-like weapons are usually only a single tool for someone else.

 

[argo]

Spells require line of sight to target and, more importantly, line of effect to cast. Line of effect is blocked by cover however the SRD notes that

An otherwise solid barrier with a hole of at least 1 square foot through it does not block a spell’s line of effect. Such an opening means that the 5-foot length of wall containing the hole is no longer considered a barrier for purposes of a spell’s line of effect.

Since humanoids do not fill their space completly it is readonable to conclude that there is at least a 1 square foot gap through the "three rows of fighting humanoids" giving the spellcaster line of effect.

BUT...

Fireball is a bit different from most other spells in that it requires more than just line of effect. It's description states that

You point your finger and determine the range (distance and height) at which the fireball is to burst. A glowing, pea-sized bead streaks from the pointing digit and, unless it impacts upon a material body or solid barrier prior to attaining the prescribed range, blossoms into the fireball at that point. (An early impact results in an early detonation.) If you attempt to send the bead through a narrow passage, such as through an arrow slit, you must “hit” the opening with a ranged touch attack, or else the bead strikes the barrier and detonates prematurely.

Which means there is a chance that the caster could hit one of the combatants with the bead and prematuerly detonate the fireball. I would resolve the attack like this: the caster needs a 1 sq ft opening for line of effect which would be a Tiny object (+2 size mod) and he is firing through a melee so he needs to take care that one of the combatants doesn't step in his way (+4 mod, firing into melee) for an AC of 10 +2 +4 = 16, have the caster make a ranged touch attack against AC 16 and if he fails the fireball impacts in the melee and detonates.

Hope that helps.

 

[SteveC]

I have looked thru the rule books and cannot find anything to help solve this question I have regarding targeting of area of effect spells like Fireball.

Could a short spellcaster (Gnome, Halfling, etc) target a fireball to go off in an area behind three rows deep of fighting humanoids? If he were firing an arrow, he would need precise shot AND the target would have cover. Yet, according to the rules as I've read them, all those fighting people in front of him don't affect his ability to pinpoint one specific spot on the grid that will provide maximum enemy exposure to the blast.

What about targeting a fireball so that allies are just outside the blast radius (I mean they are right next to a square that is fully in the blast). Is that "legal" or "Fair". Should I use the grenade-like scatter table for thrown items, or is that hindering the spellcasters abilities too much.

Generally speaking, the "1 foot clearance" rule for line of effect gets a spell caster past needing to make rolls to hit for most spells, since it is reasonable (in my opinion anyway) to cast through allies and assume you can get that much clearance. However, fireball has that nasty line in in that argo quoted: If you attempt to send the bead through a narrow passage, such as through an arrow slit, you must “hit” the opening with a ranged touch attack, or else the bead strikes the barrier and detonates prematurely.

The way I handle it is to make use of the Throw Splash Weapons rules, which have you roll against AC 5. I'd apply the +4 cover bonus if there are characters in the way. Additionally, I still use the 3.0 rules for cover, so I apply the +4 bonus to AC for each character between the caster and the target. If the caster fails his roll, I compare the roll to the touch AC of each target in the way, from nearest to farthest, and if any of the targets are hit, the fireball goes off at that point. If everyone has a good enough touch AC, the missile may still hit the right spot. If the caster can't even hit AC 5, I use the scatter rules to determine where the shot falls.

Is that the official way to handle it? As far as I've seen, yes, but I haven't seen any official rules for how it's supposed to work. The result has been satisfactory for my group in any case.

 

[shilsen]

Sure. It's a kind of magic.

 

[D+1]

As noted you need line of sight and line of effect. Fireball is no different than any other spell the player might try to cast at that location except 1) if there is cover it can impact upon before it reaches the intended detonation point it can detonate on the cover, and 2) you can at least ATTEMPT to place a fireball through a very small opening for which the spell description has specific rules. In every other manner handle Fireball as you would any other spell.

People look at that description of putting a fireball through a small opening and immediately start forgetting about the normal rules. None of those house rules are necessary as the regular game rules apply just fine.

 

[Ogrork the Mighty]

I would say no, a spellcaster cannot target the point of origin for a Fireball immediately behind a group of monsters (assuming the monsters are between the spell caster and the point of origin and the spell caster is not looking down from above). Also, for the purposes of this post, I'm working under the assumption that there are enough monsters (e.g. "three rows deep") to effectively block line of effect (a couple monsters probably wouldn't be enough).

I say that b/c the PH (p. 176) clearly states that "a line of effect is a straight, unblocked path that indicates what a spell can affect. A line of effect is cancelled by a solid barrier."

and

"You must have a clear line of effect to the point of origin of any spell you cast, such as the centre of a Fireball."

Now, that being said, the spell caster could put the point of origin X feet off the ground (depending on the height of the monsters) since Fireball is an area effect spell. But remember, the point of origin must be at an intersection so it must be in increments of 5 feet off the ground.

My 2 cents.

 

[Ridley's Cohort]

Now, that being said, the spell caster could put the point of origin X feet off the ground (depending on the height of the monsters) since Fireball is an area effect spell. But remember, the point of origin must be at an intersection so it must be in increments of 5 feet off the ground.

Exactly.

In theory the spellcaster may be required to make a ranged touch attack against AC 9 (give or take) to place the Fireball exactly where he wants it through a crowded battlefield.

In practice the spellcaster can usually aim 6 or 12 feet off the ground to completely avoid obstructions and not be required to make the attack roll. If the monsters are tall and the ceiling high he may even be able to safely hit his targets from above while they are mixed up with allies.

 

[Majere]

An arrow slit is about 1" wide
I dont think we are trying to claim it is anything like that hard to fire past someone.
Just let em do it, it really wont break the game trust me

Majere

 

[Saeviomagy]

Which means there is a chance that the caster could hit one of the combatants with the bead and prematuerly detonate the fireball. I would resolve the attack like this: the caster needs a 1 sq ft opening for line of effect which would be a Tiny object (+2 size mod) and he is firing through a melee so he needs to take care that one of the combatants doesn't step in his way (+4 mod, firing into melee) for an AC of 10 +2 +4 = 16, have the caster make a ranged touch attack against AC 16 and if he fails the fireball impacts in the melee and detonates.

Cool. That means that I GUARANTEE'D hit my target by failing a roll against a square behind him.

And if I HIT him with the bead, that means he doesn't get a save, right? He can't possibly escape the blast - the bead itself hit him.

In fact - I aim for his earhole. Then the bead hit him IN THE HEAD and detonated!

Which is all stupid.

Creatures do not provide a solid barrier, and therefore fireball doesn't need to roll to miss them.

Or 'accidentally' hit them as the case may be.