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NitroIndigo
Since: Jun, 2021

A storytelling method where the main story is written in a generally fun and lighthearted tone with occasional serious moments, but the side content is where all the good stuff is hidden (like worldbuilding, iconic character moments, serious/heavy themes, etc.) to the point where you'd need to actively consume the side content to follow along with the overarching narrative.
One example I can think of is the currently Korean-only gacha game "Trickcal Re:vive" where all the lore surrounding the "cult" the player character leads and the laws of the world itself, alongside a lot of character moments the fanbase loves, is presented in great detail in limited-time events called Theme Theaters while the main story serves more like an introductory vehicle for establishing the world the player interacts with, at least for Season 1. This storytelling method has been affectionately called "Trickcalism" by the community.