It was a fun little top-down 3rd person shooter! As a quick side note, before I forget (as I'm leaving a comment right after playing): was the whole thing about "a thousand years" in reference to Myth's song, "Journey Like a Thousand Years"? On one hand, it's not Council/Promise's song... but on the other, the "thousand years" thing seems so deliberately repeated.
Anyways, as for the game itself, it was fun. I'm not particularly skilled at these sorts of games so I appreciated that stray enemies in the world remained dead after killing them. So I abused that and kept running back to the altar rather than using the time restoring items. That way, I can save those restorative items during the hordes.
I definitely thought it was a neat idea, having time also serve as your health and, once your gun starts overheating, also your "resource" for shooting. A lot of things really ended up tied to "time" so it was very appropriate for this game jam.
What I did wish there was more of as I was playing was enemy variety. I was preparing myself to have to deal with different kinds of enemies but in the end, the two enemies there were ended up being similar in function as well, just one took one more hit than the other in exchange for having a larger hitbox.
Now, I don't know if you were going for a bit of an unsettling/horror-ish vibe but as someone who scares easily, I personally felt that way. Though I do think, in a way, it is appropriate, intentional or not, given the tension I'm supposed to feel.
Overall, I think this was pretty well done and I'm curious to see if you will expand on this game after the game jam ends. I hope so given teasing you did at the end of the game.