Is there a way to stop gaining experience in World of Warcraft?

From WoW Wiki: Level Locking

To keep your character from leveling higher for any reason, follow these steps:

For the Horde faction:

1. Go to the Hall of the Brave, Valley of Honor in Orgrimmar.
2. Look for and talk to Horde Slahtz.
3. For 10g he will put a hold on all experience points earned.

You can enable your experience again by seeing Slahtz and paying another 10g.

For the Alliance faction:

1. Go to the War Room, Stormwind Keep in Stormwind City.
2. Look for and talk to Alliance Behsten.
3. For 10g he will put a hold on all experience points earned.

You can enable your experience again by seeing Behsten and paying another 10g .

You can talk to Slahtz (Horde) or Behsten (Alliance)

They will charge 10g each time you decide to switch to gaining/not gaining experience

You can lock your level by going to the an Experience Eliminator NPC(Alliance/Horde) and paying for it:

If you do not want to gain XP (ex. for the purpose of making a Twink), you can visit Behsten or Slahtz to turn off all experience gains. It costs 10g to disable and another 10g to enable it.

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