Story: It seems your girls can't wait for their presents. How will you make them happy? They have some ideas for spending a cold, winter night together, for sure.
Every eight hours the event will assign you five missions. These are randomly selected campaign missions based on how far into the campaign you have unlocked. Each mission you run grants event tokens based on the number of stars earned on the mission.
Three star missions award 300 tokens, allowing you to earn up to 4500 tokens per day, or 27000 tokens across the entire event.