Is Entangle supposed to be limited by the available vegetation?

[Gantros]

You don't need line of effect because the roots are not the target of the spell.

The fact that plants must be in the area of the spread doesn't make them the target of the spell nor require line of effect to them. As noted specifically, line of effect determines the area that can be affected, not WHAT can be affected. As far as line of effect rules are concerned the target is still the area - not the roots.

I think you missed the second half of the Line of Effect rule... "You must have clear line of effect ... to any space in which you wish to create an effect"

Entangle's area of effect is a spread, which doesn't pass through solid barriers that block line of effect. It's further limited to plants within the spread area, so it can't pull plants into the area from the outside. If the only nearby plants are on the other side of a solid wall, the spell isn't going to do anything, because there are no plants in the area of effect.

One oddity of Entangle though is that even if the only vegetation in the area of effect is a single potted plant sitting on one side of it, it can still entangle any number of creatures on the opposite side of the area up to 80 feet away, even around corners! That would make for quite a sight...

 

[Wulf Ratbane]

I think you missed the second half of the Line of Effect rule... "You must have clear line of effect ... to any space in which you wish to create an effect".

Quick diversion re: line of effect and spreads.

Your wizard is standing at the top, facing towards the end of a 60 foot long, dead end hallway.

He casts cloudkill into this hallway, centered 30 feet in front of himself.

Describe what happens next.

Spell description here:
[sblock]Cloudkill

Conjuration (Creation)
Level: Sor/Wiz 5 Components: V, S Casting Time: 1 standard action Range: Medium (100 ft. + 10 ft./level) Effect: Cloud spreads in 20-ft. radius, 20 ft. high Duration: 1 min./level Saving Throw: Fortitude partial; see text Spell Resistance: No

This spell generates a bank of fog, similar to a fog cloud, except that its vapors are yellowish green and poisonous. These vapors automatically kill any living creature with 3 or fewer HD (no save). A living creature with 4 to 6 HD is slain unless it succeeds on a Fortitude save (in which case it takes 1d4 points of Constitution damage on your turn each round while in the cloud).

A living creature with 6 or more HD takes 1d4 points of Constitution damage on your turn each round while in the cloud (a successful Fortitude save halves this damage). Holding one’s breath doesn’t help, but creatures immune to poison are unaffected by the spell.

Unlike a fog cloud, the cloudkill moves away from you at 10 feet per round, rolling along the surface of the ground.

Figure out the cloud’s new spread each round based on its new point of origin, which is 10 feet farther away from the point of origin where you cast the spell.

Because the vapors are heavier than air, they sink to the lowest level of the land, even pouring down den or sinkhole openings. It cannot penetrate liquids, nor can it be cast underwater.[/sblock]

 

[Man in the Funny Hat]

I think you missed the second half of the Line of Effect rule... "You must have clear line of effect ... to any space in which you wish to create an effect"

Entangle's area of effect is a spread, which doesn't pass through solid barriers that block line of effect.

Spread effects turn corners which is what primarily makes them different from Burst effects. You do NOT need to see all areas that are affected by a spread. For a spread you only need line of effect to the point of origin. A burst needs line of effect from caster to point of origin and then from point of origin to all areas that it affects. Not so for a spread.

It's further limited to plants within the spread area, so it can't pull plants into the area from the outside. If the only nearby plants are on the other side of a solid wall, the spell isn't going to do anything, because there are no plants in the area of effect.

Plants of some kind are logically necessary for the spell to have any effect. All I was saying is that PLANTS are not the target of the spell. The target of the spell is an area, not the plants IN that area, and the EFFECT of the spell is to cause plants to hinder movement of creatures in the area. You don't target plants, you don't need line of effect to the plants - just to the point of origin of the area. If there AREN'T any plants in the area, then you are correct that the spell can't have any effect, but that's not because of the line-of-effect rule but effect-description issues.

One oddity of Entangle though is that even if the only vegetation in the area of effect is a single potted plant sitting on one side of it, it can still entangle any number of creatures on the opposite side of the area up to 80 feet away, even around corners! That would make for quite a sight...

The spell description specifically notes that the DM can "alter the effects somewhat" "based on the nature of the entangling plants". If the area is solid stone with one potted plant around a corner the DM is free to rule that a single geranium or chrysanthemum won't hold creatures 80' away. He can rule that a freshly cut branch of a tree qualifies as "plants". He can rule that an oak tree holds better than a willow tree. He can also rule that unplanted, but viable seeds can effectively be used as a material component in the absence of other plants in the intended area.

Personally, I don't need any spell description to tell me what I can and can't rule as DM, but "adjusting effects" of the spell can be read to give LARGE amounts of arbitrary power to the DM to limit the spell if desired. It's then up to the DM to use that power wisely and consistently.