Thanks for playing! The idea was that the NPCs hint towards mechanics (ex. level 1 or the second NPC in level 4) or what kind of cipher is being used through act 1 (split acts 1-3 into 5 levels each). It definitely could be easier, like I found how to copy the riddle to clipboard a bit after the deadline. It isn't a bug that the 2nd NPC is standing where it is in level 4, but is perhaps too subtle. It can be passed by platforming, but unlike most of the other levels there isn't a way back if you get to the relic after that point.
Viewing post in World Alert: Purge the Dark jam comments
Oh, I was able to figure out that the 2nd NPC in level 4 was standing on an invisible platform so that's not an issue for me! Where I got stuck was the uppermost long horizontal corridor after jumping across the chasm and reaching the riddle. One of the eyes started watching me as soon as I reached that corridor, and since I couldn't solve the riddle (is that what you mean by getting the relic?), I didn't have the extra brightness and couldn't run down the corridor in time.
Yeah that's the issue with level 4: if you jump down to get to the riddle (relic) but don't solve it, you can't make it past the eye corridors - and there's no way back up to the platformer solution without restarting the level - something I missed during development. Try using that same NPC hint elsewhere.