First of all, before reading this topic, I want to warn you that, even though the subject is "outdated" (I found out that this game started around November 2015), the "game" spread in other countries during the time, even in Romania.
So, there is a game called the "Blue Whale", which goes on the social network ВКонта́кте/VKontakte (known as VK (https://vk.com/)). In that game, you have to play it for 50 days in a row, fulfilling each day a random challenge, plus, you need to send a photo after the task is ended to the "curator". If you refuse to continue, If you die, you win. If you don’t, we will help you.
Here is a video from Russia Today (https://en.wikipedia.org/wiki/RT_(TV_network)), published on May 2016, where the people working there explained how the "game" works.
https://www.youtube.com/watch?v=eZiV49EDcg0
Between November 2015 and May 2016, 130 young Russian people ended the game (commited suicide). From what I understood, the hashtags were banned and the guy who started all this is believed to be Filip Budeikin, who has beeen arrested in November 2016. Well, the case has been spread in Romania recently, where 5 12 year-olds were taken to the ICU after being found with serious breathing problems, which were caused by a challenge of the game.
To check the story in depth, here are some sources:
"The Blue Whale" - Five asphyxiated children at school (in Romanian) (http://www.digi24.ro/stiri/actualitate/social/balena-albastra-cinci-copii-asfixiati-la-scoala-689679)
http://iheartintelligence.com/2017/02/22/blue-whale-suicide-game-social-media/
http://www.rferl.org/a/russia-teen-suicide-blue-whale-internet-social-media-game/28322884.html
http://www.theglobeandmail.com/arts/television/russell-smith-the-blue-whale-game-and-how-the-news-can-imitate-art/article34302146/