spring attack and line of sight

[wordelo]

do I need line of sight to start a spring attack?

for example: party is behind an illusory wall. the monster (quickling to be exact) knows it's illusory but can't see past the wall. can the quickling spring attack the party moving back and forth through the illusory wall?

I am told that because it is considered a full-round action I must declare a target (which I can't because I can't see a target but I know it's there via other senses) before I start the full round action.

OR

I start spring attack action and move until I see a target and attack that target then move away completing the spring attack.

[Nigrescence]

Spring Attack wrote:

Spring Attack

As a full-round action, you can move up to your speed and make a single melee attack without provoking any attacks of opportunity from the target of your attack. You can move both before and after the attack, but you must move at least 10 feet before the attack and the total distance that you move cannot be greater than your speed. You cannot use this ability to attack a foe that is adjacent to you at the start of your turn.

The wording seems to suggest that you must have an already declared target (therefore you are aware of them, even if you can't see them) due to its negation of attacks of opportunity from the target.

How do you know it is illusory but can't see past? Did someone else make a save and then let you know? Did a Spellcraft check succeed so they could tell you it is illusory?

More importantly though, how do you ACTUALLY KNOW they are there? They may have teleported or moved. You say other senses, but I don't know what those are. Do you have Tremorsense or Scent? Something similar? If you do have that and you KNOW they are there, because you can sense them, then clearly you can still identify targets properly and so it is not a problem. If not, unfortunately memory is not a 'sense', and you cannot know that nothing has changed since you last were aware of the target's location. So even if you remember where they were standing and suspect they are still ready to fight you, you cannot properly actually sense them and attack as a declared target.

Point is, there is still information you are leaving out that is important to determine whether you can or not. What other senses?

As to the part of moving through the illusory wall, you are free to attempt it, given your knowledge, but remember that your character might actually have doubts about the illusion. It seems real to them, after all. But you can charge on into the wall freely trusting in your information that it is not real, and find out the hard way.

Illusory Wall wrote:

Illusory Wall

It appears absolutely real when viewed, but physical objects can pass through it without difficulty.

You clearly CAN move through it. It is only illusory after all.

[wordelo]

ok I used illusory wall to simplify things but it clearly has only made it more difficult.

The real situation is magical vines hanging from the ceiling that allow enemies to pass through freely these vines still block line of sight.

perception checks to hear creatures on the other side of a sight blocking obstacle is what I meant by senses. they do know a creature is there. like a talking invisible creature.

other examples include fog cloud, obscuring mist, deeper darkness(target on the other side not inside) to make a spring attack moving through the mist/fog/darkness until you see a target that you know is there somewhere. (still moving ten feet even after a target has been seen)

or another way to put it can I spring attack an invisible creature if I know what square he is in? (with 50% miss chance of course)

I can target the square with attack spells, I can target it with area spells like fireball, but I know I cannot target it with charm person, or magic missile. Can I target a square with spring attack but in the action of making the spring attack I then completely see the creature negating any miss chances.

all this are examples of a yes or no question

do I need line of sight to start a spring attack?

[Skylancer4]

Generally speaking, if an ability calls for a target, line of sight is required. Otherwise, like you mentioned, you are attacking an area are which strictly speaking isn't the same.

Think of it like this, you can't avoid attacks from an opponent you don't even know is there, and that is exactly why spring attack is so useful.

[wordelo]

I will be able to see my target eventually. I can make a regular attack into any square even if I'm blinded. so let me give you more examples of similar actions

I attack a square where an invisible creature is at via the spell invisibility with an unarmed strike. That creature takes an attack of opportunity on me with a weapon ending the invisibility spell. do I still get a 50% miss chance?

the answer would be no because he is now visible and can continue with my punch and it says loosely that attacks of opportunity are made before the action that triggered it. like when a creature tries to stand up from prone provoking an attack of opportunity. the attack is made as if the creature is still prone.

another way to put it

is spring attack declaring targets the exact same as declaring targets for magic missile? because you need line of sight to declare targets for magic missile. even if you know what square an invisible creature is via blind sense, guessing, detect magic, being told that a guy is in that square you still won't be able to target him with magic missile.

the old adage "I'm attacking the darkness." never actually works... but that's part of the joke.

OK let me throw a curve ball. it says that spring attack is a full-round action... not going to argue that.

so as a standard action I can start a full-round action (let's say in a surprise round) starting a spring attack and then finishing it using another standard action next round. how would that work?

I'm going to answer my own question and say that it doesn't work at all because it says it can't be used with a select few full-round actions that involve movement (charge, run, withdraw)

so this would be move up as surprise round, during first round attack and then move away (using acrobatics and mobility feat if failed) to set up spring attack for second round.

[Archaeik]

Targeted spells are "see or touch".

Further, targeting is done after you finish casting, not "as part of". (even if it is commonplace to know your targets before you start casting)

I don't read Spring Attack to require target acquisition before movement (but it is allowed to facilitate moving passed/behind for flank).

[Talon Stormwarden]

Spells require a target, as per the spell targetting rules. Physical attacks do not. Just because the feat Spring Attack uses the work "target" doesn't mean you all of a sudden switch to the spell rules for a physical attack. The word "target" is used throughout the rules, only when it is used in the context of a spell that has specific targets (see, even I did it) do you invoke the spell targeting rules.