Oct 2021 Event had a new system that allows you to gift items to NPC to increase affection, and get rewards.
But did you know there are 5 Hidden missions to unlock extra rewards?

0:00 Intro
0:21 New System Explained
1:01 Hidden Mission Guide
2:11 Sign-in Event
2:34 Pray Pack Exchange Event
3:12 Food Fest Event
3:24 Moe Day Event
3:37 Donation Event
3:58 Past Event HG Box
4:10 Abyss Mount BCC Box
5:04 New Weapon Skin Preview