The League of Legends mystery gift program is still running and so was not just something for Halloween. We are told that you will be able to make use of these special skins until the next event, although we have no idea when that will be. So for now we would advise you to take full advantage of these gifts.
When the mystery gift was first announced last month fans of the League of Legends were unaware of its cost, or if it would even be free. However, it did not take long to work out that the game developer was not going to allow you to give a skin away completely free.
Those of you who kept asking how much these would cost finally realized that these gifts were going to cost 490 RP each, which seemed a little silly because you could purchase a skin for just 30 RP more.
When you visit the League of Legends website it does state that Mystery Gifting runs for the duration of Halloween, but here we are several days later and they are still available.
It is not just mystery gifts that you can take advantage of during the Harrowing Event; Skins, Ward Skins, and other Rewards are also available. You can learn much more by visiting the official website.