Source: Tal'Dorei Campaign Guide Reborn

Wondrous item, legendary (requires attunement)

This cloak is made of heavy dark cloth trimmed with golden patterns, and occasionally shimmers with sparks of arcane energy. It was once worn by the famed gunslinger Percival Fredrickstein von Musel Klossowski de Rolo III of Whitestone.

Dormant. While Cabal’s Ruin is in a dormant state, the cloak has 4 charges and it regains 1d4 expended charges daily at dawn. When you hit with an attack, you can expend any number of charges from the cloak, with the attack dealing an extra 1d6 lightning damage per charge expended. If your attack strikes multiple targets, you choose one target that takes this extra damage.

When you are targeted by an enemy’s spell, you can use your reaction to absorb a portion of the spell’s energy into the cloak. The spell affects you normally, but the cloak regains a number of charges equal to the level of the spell. This property can’t be used again until you finish a short or long rest.

Awakened. When Cabal’s Ruin reaches an awakened state, you gain the following benefits:

• You have advantage on saving throws against spells and other magical effects while wearing this cloak.
• The cloak has 6 charges and it regains 1d4 + 2 expended charges daily at dawn.
• When you use the cloak to absorb a spell, you gain resistance to one type of damage dealt by the spell (your choice). This resistance then lasts until the end of your next turn.

Exalted. When Cabal’s Ruin reaches an exalted state, you gain the following benefit:

• The cloak has 10 charges and it regains 1d6 + 4 expended charges daily at dawn.