Get ready for massive Experience gains as World of Warcraft celebrates its 20th Anniversary! Starting October 22, leveling your alts has never been easier, with total Experience gains increasing by up to 65% and Reputation by 30%.
20th Anniversary XP Buff
Players receive an automatic 10% Experience and Reputation buff during the Anniversary event and must complete the repeatable Celebrate Good Fun! quest from Yllana every day to add another 10% to the total.
Warbands XP Bonus
For every character you have at Level 80, you will enjoy an additional 5% XP buff, stacking up to 25% times. This means if you have 5 Level 80 characters, you will be raking in a +25% XP bonus from 
Five Warband Mentors: The War Within.
War Mode Bonus
With War Mode enabled you will receive +10% XP and Gold.
Hallow’s End Buff
From October 18 through November 1, 
Unburdened will increase XP and Reputation gains by 10%.
Darkmoon Faire Buff
Starting November 3, Darkmoon Faire arrives, bringing the 
WHEE! buff. This additional 10% boost to Experience and Reputation lasts for 1 hour and stacks with the Anniversary event buff!
Big XP and Reputation Gains – The Breakdown
Starting October 22, you will automatically receive a 10% XP and Reputation boost that can be increased to 20% every day by completing a simple quest. For each Level 80 character, you gain another 5%, stacking to 25%. War Mode grants +10% when enabled. Hallow’s End brings a +10% XP and Reputation buff between October 18 and November 1. Two days after Hallow’s End concludes, Darkmoon Faire will start, bringing another 10% boost, leading to a total of +65% XP and +30% Reputation gains again from November 3 through November 10!