You now have the chance to befriend Gargaros, the powerful oni you meet in Terror Time, in this new event lasting from 12/12 to 1/9.
Like the last Terror Time event, there are three areas to progress in: Terror Time, Super Terror Time, and Ultra Terror Time. At the end of each area lies Gargaros where you have the chance to befriend him. The Gargaros in the Super and Ultra area are easier to befriend, Ultra being the easiest, but also hard in difficulty.
By using Camellia that you might befriend in Score Attack or in the Crankakai (who is a permanent addition), you can deal bonus damage to Gargaros that makes him easier to befriend. You can also befriend him through the means of giving him the meat category of food, which you can buy easily in the shop. Occasionally after you clear stages in the Terror Time maps, Chance Time can occur, which makes befriending Gargaros much easier.
To unlock the hidden stages in these maps: