While you cast this spell, you use the cord to create a cube that can be as small as 5 feet to as large as 50 feet on each side on a flat surface within your reach. When you finish casting, the cord disappears to become an area of containment made of light or fog. When a small creature or larger moves into or starts its turn in the area protected by the spell, the triggering creature must succeed on a Dexterity saving throw or be bound by the spell. If it succeeds, it is not bound in the spell area.
A shapechanger makes its saving throw with disadvantage. If it fails, it also instantly reverts to its original form and can’t assume a different form until it leaves the spell’s area.
When you cast the spell, you choose three of the following wards in the area of containment:
Blinding Moonlight. Bright moonlight fills the area, illuminating the space and dazes the target. The target is blinded until the spell ends.
Cloud of Wolfsbane. Gaseous toxins fill the area, clogging the air for the target. The target is poisoned until the spell ends.
Piercing Whistle. High-pitched sound fills the area, riddling the target's ears with sound. The target is deafened until the spell ends.
Silver Chains. Multiple silver chains, firmly rooted in the ground, hold the target in place. The target is restrained until the spell ends.
Teleportation Lockdown. Planar travel and teleportation magic is blocked within the area of containment.
Casting this spell on the same spot every day for a year makes this effect permanent.
At Higher Levels. When you cast this spell using a spell slot of 6th level or higher, you can increase the size of the cube by 50 feet for each slot level beyond 5th. Thus you could protect a cube that can be up to 100 feet on one side by using a spell slot of 6th level.
* - (50 feet of silver cord worth a 100 gp)