Echo

Echo is a perilous realm, this ruined landscape results from pocket planes and lost planes crashing on one another, creating a single chaotic realm inhabited by the wandering souls of the dead lost in the void and on lost planes. Echo is a plane of chaos, the junkyard of all other planes.
Once an individual from the outer planes die, normaly its soul go to the void and is lost to eternity. Sometimes those lost souls drift to echo, and end up in the plane of chaos. Here, the chaotic energy turns magic wild and changes the matter and energy. The junk of all the planes ending her rot and rust slowly as it float and created sharp landscape, petrified demon, devils, and angels serve as monuments, embed in the landscape. Fragments of more ordinary landscapes - bits of forest, meadow and ruined castles drift through the disorder. The whole plane is a nightmarish riot.

Features

Turn to stone

At the end of each long rest taken on the plane, a visitor must make a DC 10 Wisdom saving throw. On a failed save, the creature gains one level of exhaustion, which can’t be removed while the creature remains in Echo. If the creature reaches six levels of exhaustion, it doesn’t die. Instead, the creature permanently transforms into a stone statue.

Rust

At the end of each long rest taken on the plane, every non-magical object made of metal start to rust. If the object is an armor or a shield, it takes a permanent and cumulative −1 penalty to the AC it offers. Armor reduced to an AC of 10 or a shield that drops to a +0 bonus is destroyed. If the object touched is a held metal weapon, the weapon takes a permanent and cumulative −1 penalty to damage rolls. If its penalty drops to −5, the weapon is destroyed. Nonmagical ammunition made of metal are destroyed instantly.

Unraveling Magic

The source of magic is damaged or corrupted in this region. Magic is unpredictable, and strange results occur when a creature casts a spell. Consider rolling on the Unraveling Magic Effects table when the following circumstances occur in the region:
Any charges are expended in a magic item.
A spell slot of 1st level or higher is expended.
A dragon, a fey, or an elemental of challenge rating 5 or higher dies.

Unraveling Magic Effects