You can opt out of this event by talking to Glynereth and asking for Mimic Repellent.
Once you have the repellent, it stays with you until you speak to her again and ask for it to be removed, or until the end of the event.
One thing to know is this only effects chests that you personally open. If someone else in your party opens a chest, a Mimic could still spawn, depending on whether they have asked for repellent or not.
- Chests can be ransacked: after the sixth time, you will no longer be able to get a mimic, and will receive the message You have looted this chest too often to get a mimic.
- Note that this limit is per character, like all other ransack mechanics, and not per account
- You cannot get a mimic if you are more than 4 levels over the quest level. This again only applies to the character opening the chest.
- If there is someone in the party that is within 4 levels, they can open the chest and cause a mimic to spawn. After killing it, everyone in the party will still get a Mimic Token