The winter festival is held usually in the month december and january. The most common question we get is: is it worth it?
Hell yeh.. Althrought the events in the festival are simple, they do earn you so called gifts. You can then share your gift with 4 other ppl in your party. The gifts really vary from simple stuff, to good mounts and companions.
Last festival I received four purple companions and two blue mounts from gifts alone.
However be aware! There are also simple laterns, that look the same as the gifts, but are not. These are fake and you won't get any rewards from them.
If you did earn gifts, save them. In chat you will see ppl asking to party up for a number of gifts. This means everyone in the group need to have at least the number of gifts to share.
I highly advice only to share gifts with others in your alliance or guild! Just call your gifts in the alliance chat.
You can take a risk and open them with strangers in your party, however; there are scammers. These people pretent they have several gifts, but actually open laterns. The visual effect is the same, but you don't get rewards. If you let players open one by one, you will notice the scammers. Report them in chat or to the leader of the guilds.
For a nice and complete winter festival guide, take a look at this video: