Marriage was released alongside Valentine's Day 2014 on 14 February 2014 (V1.138).
Your spouse is officially called your "soul mate" (not to confuse with soulmate maps).
You have a higher chance of being selected for shaman together in dual shaman maps.
Marrying
To marry someone, you just have to enter the name of a user in the search box in the friend list (bottom left button with heart logo) and then click the marry button.
You could also press on someone's username and then press "Marriage proposal" from there.
The user will receive a marriage proposal, which they can refuse or accept. If accepted, the partner's name is displayed on the profile and they will always be at the top of the friend list.
Divorcing
To divorce someone, click on their username from the friend list and select "divorce." The player will remain in the friend list.
It takes 1 hour to be able to marry again after divorcing someone.
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