Big/hu
From xat wiki
(BIG) - Big smilies LIMITÁLT EPIC
Template:Img is only allowed in User: namespace. Use [[File:]] (more on that here) or Template:Gallery on articles instead.
The Big power allows you to send a big smiley in the chat.
When Big is enabled, and you send a message that contains one smiley and no other text or smilies, it will be enlarged. If the message contains any text, or another smiley, it will be unaffected by Big.