This page lists all of the enchantments added in AbyssalCraft, with information on their usage.
Sword Enchantments
Coralium
The Coralium enchantment functions like the Fire Aspect enchantment. Upon hit, it applies the Coralium Plague (instead of setting the entity on fire).
Dread
The Dread enchantment works like the Coralium enchantment, except it applies the Dread Plague.
Light Pierce
The Light Pierce enchantment works like Smite/Bane of Arthropods, but is effective against Shadow Mobs (such as the Shadow Creature, Shadow Monster and Shadow Beast).
Armor Enchantments
Iron Wall
The Iron Wall enchantment is a "anti-knockback" enchantment; ie. it negates any knockback from enemy attacks.
Potion Effects (more explained):
Coralium Plague deals 1 heart of damage per second (at a rate between Poison and Wither).
Dread Plague deals 1/2 heart of damage per second, while also reduces your food bar (like the Hunger potion effect does, de-saturating it).