p.s. One last suggestion: make the true ending rely on a game-spanning secret. In a secret-hunting game, discovering the secret built up from clues that have been in plain sight (but only given context near the very end) is just the best. ><
Um, if you’ve played Tunic, the true-end puzzle of that is what I mean. The true-end puzzle of Outer Wilds also does it (and its dlc does it again!). (edit: Leap Year might also be a good game to look at)
For this game, maybe it’s some sort of song, with pieces scattered around the world in weird symbols? IDK. It’s a lot of work to pull off, but I think it’s worth trying for. ᕦ(ò_óˇ)ᕤ