# Can you use a Wall of Sand to blind a creature without obscuring it?

Recently, I was taking a look through the Wizard spell list, and the Wall of Sand spell sparked my interest:

You conjure up a wall of swirling sand on the ground at a point you can see within range. You can make the wall up to 30 feet long, 10 feet high, and 10 feet thick, and it vanishes when the spell ends. It blocks line of sight but not movement. A creature is blinded while in the wall’s space and must spend 3 feet of movement for every 1 foot it moves there.

Blinded is a relatively powerful condition, and applying it without a save seems very strong. However, the Wall of Sand spell also blocks line of sight. If a creature also becomes heavily obscured by the wall, it would negate many of the benefits of applying the blinded condition.

It seems like a caster could circumvent the issue by placing the wall to partially intersect a creature. For example, a Wall of Sand could include half of the squares occupied by a large creature. Because at least one of the creature's squares is within the wall, the creature is within the wall, and therefore blinded. However, at least one of the creature's squares is not within the wall, so the creature is not heavily obscured.

Would this strategy work under the variant rule "Playing on a Grid"? Could this strategy also be applied to Medium-sized creatures?

# Wall of Sand can sometimes blind a creature without obscuring it

The Dungeon Master's Guide (p. 251) states that, when discussing Line of Sight using a square or hex grid:

To precisely determine whether there is line of sight between two spaces, pick a corner of one space and trace an imaginary line from that corner to any part of another space. If at least one such line doesn't pass through or touch an object or effect that blocks vision [...] then there is line of sight.

For a creature that is Large in size or larger, the DMG says they take up 4+ squares on a grid. The creature therefore can both be in the wall's space and have parts that are unobscured from certain angles.

When not using the Grid variant, it seems reasonable to even allow Medium or Tiny creatures to be affected in this way because a creature does not have to be entirely within a spell's AOE to be affected. If this were not the case, then a spell such as Thunderclap with a small AOE would be unable to affect any creatures that are Large or larger.

RAW says the wall removes line of sight, so if a creature is on the other side of the wall or completely within it is blocked from sight. Many conditions can be applied without a save. Usually without damage or lesser damage. this spell is entirely for blinding and /or obscuring yourself, others, or enemies. The blinded condition ends when no longer in the area of effect.

• Could you please clarify your answer? This don't seem to answer my question. – Joshua May 3 '20 at 21:17

Something similar came up in a game I was running with wall of light. The primary difference here is that wall of light is 5' thinner than wall of sand, but the mechanical issues remained.

On the first casting, one of my players grappled a NPC and put him in the wall. They asked what happens and I ruled that the NPC was in the wall, the player wasn't, and that others could still attack the visible NPC.

They went great!

A few rounds later, the NPC grappled a player and did the same thing to them. This time, they did not like the result.

We came to the final decision that creatures held in a wall that is opaque are not visible to attacks. So disadvantage on attacking them and no line of sight for any spell that requires it.