Runes are a new feature in WoW Season of Discovery (SoD) that allow you to customize your class and spec with additional abilities and passives. They are engraved on your gear and can be swapped out of combat. There are 12 runes 
available for each class, split among Gloves, Legs, and Chest. Runes are soulbound and cannot be traded, but you can help other players get them.
Rune Engraving emerges as a fresh addition unique to SoD and allows each class to tailor their gameplay experience by unlocking new unique abilities. It is a mechanism enabling the collection, learning, and utilization of previously unprecedented class abilities within WoW Classic. These abilities can completely change your class' gameplay and provide a whole new gaming experience within your favorite game.
During the initial SoD level band capped at level 25, players will only have access to the Rune Engraving for three slots: Chest, gloves, and Legs. As players progress into higher levels and later content-level bands, they'll be able to engrave runes onto more gear slots.
Some of the Features and Effects of Runes Are:
Runes can grant new or improved spells, talents, or mechanics that can alter the roles and playstyles of each class and spec. For example, Warlocks can tank with their pets and 
Demon Armor, Mages can heal with Arcane Healing and 
Arcane Barrier, and Paladins can DPS with Holy Power and 
Templar's Verdict.
Runes can also provide useful buffs, debuffs, or effects that can enhance your performance and survivability in different situations and content. For example, Elixir of Giant Growth can increase your size and strength, Potion of Curing can remove curses and diseases, and Flask of Petrification can turn you into stone and make you immune to damage.
Here Is a List of Rune Engravings Available for Every Class in SoD:
Druid Runes
Chest
Fury of Stormrage
Wild Strikes
Survival of the Fittest
Living Seed
Gloves
Wild Growth
Mangle
Lacerate
Sunfire
Legs
Skull Bash
Lifebloom
Savage Roar
Starsurge
Hunter Runes
Chest
Cobra Strikes
Lone Wolf
Master Marksman
Aspect of the Lion
Gloves
Beast Mastery
Carve
Chimera Shot
Explosive Shot
Legs
Flanking Strike
Kill Command
Serpent Spread
Sniper Training
Mage Runes
Chest
Regeneration
Fingers of Frost
Burnout
Enlightenment
Gloves
Rewind Time
Ice Lance
Arcane Blast
Living Bomb
Legs
Living Flame
Mass Regeneration
Arcane Surge
Icy Veins
Paladin Runes
Chest
Seal of Martyrdom
Divine Storm
Horn of Lordaeron
Aegis
Gloves
Beacon of Light
Crusader Strike
Hand of Reckoning
Legs
Divine Sacrifice
Inspiration Exemplar
Avenger's Shield
Exorcist
Rebuke
Priest Runes
Chest
Strength of Soul
Serendipity
Void Plague
Twisted Faith
Gloves
Shadow Word: Death
Circle of Healing
Penance
Mind Sear
Legs
Prayer of Mending
Homunculi
Shared Pain
Power Word: Barrier
Rogue Runes
Chest
Deadly Brew
Just a Flesh Wound
Quick Draw
Slaughter from the Shadows
Gloves
Mutilate
Shadowstrike
Saber Slash
Shiv
Main Gauche
Legs
Between the Eyes
Blade Dance
Envenom
Shaman Runes
Chest
Dual Wield Specialization
Healing Rain
Overload
Shield Mastery
Gloves
Lava Burst
Lava Lash
Molten Blast
Water Shield
Legs
Ancestral Guidance
Earth Shield
Shamanistic Rage
Way of Earth
Warlock Runes
Chest
Lake of Fire
Master Channeler
Soul Siphon
Demonic Tactics
Gloves
Metamorphosis
Shadow Bolt Volley
Chaos Bolt
Haunt
Legs
Everlasting Affliction
Incinerate
Demonic Grace
Demonic Pact
Warriors
Chest
Blood Frenzy
Flagellation
Raging Blow
Warbringer
Gloves
Devastate
Endless Rage
Single-Minded Fury
Victory Rush
Quick Strike
Legs
Consumed by Rage
Frenzied Assault
Furious Thunder
Some of the Ways to Get Runes Are:
If you want to get runes in SoD, you will have to do some exploration and adventure in the world of Azeroth. Some runes are easy to obtain, while others are hidden and require more effort and cooperation. You can also help other players get the runes you already own by sharing the information or joining them in their adventures. If you have no time or are tired of doing quests or exploring dungeons, the simple way is to buy fast WoW Season of Discovery boost from a third party, which can help you level up your character fast.
Completing Quests
Some quests will reward you with runes as part of their objectives or rewards. For example, the quest The Missing Diplomat will give you the Rune of Diplomacy, which allows you to talk to hostile factions. You can find quests that give runes by looking for the rune icon on the quest log or the map.
Exploring Dungeons
Some dungeons will have runes hidden in their depths, waiting for you to discover them. For example, the dungeon Blackfathom Deeps will have the Rune of Blackfathom, which grants you a new ability called Blackfathom's Fury. You can find runes in dungeons by looking for clues, solving puzzles, or defeating bosses.
Finding Clues
Some runes will have clues scattered around the world, leading you to their locations. For example, the Rune of the Wilds will have clues in the form of animal tracks, feathers, and bones.
I hope this information helps you understand and enjoy the Rune or Rune Engraving features in SoD. Enjoy your game.
Related Links:
Season of Discovery Tier List Guide: DPS, Healer, and Tank Rankings
