Scroll of curse armour
Version 0.14: This article may not be up to date for the latest stable release of Crawl.
Reading a scroll of curse armour will curse a worn piece of armour of your choosing, allowing you to receive Ashenzari's defensive skill boosts and improving the rate at which you gain piety from him. They do not generate naturally, but Ashenzari-worshipers can produce them by praying over a scroll of remove curse.
History
Prior to 0.14, scrolls of curse armour would be naturally generated as loot, just like any other scroll.