I've heard you can get a Dusk Stone before the 8th gym, or somewhere post-game. My bro is looking for one too, now I'm on the hunt for it :d Anywho, just caught the titular legendary of the game. One Ultra Ball and done. Must have a capture rate of 45... Still, that was really intense. Actually, that last half after the 7th gym was incredibly intense, and very dark I lost count of how many times I "wtf?!" while reading the text XD I don't have the game open now, but nearly everyone is at lv60 or above. My bro took the time to Aime all his Pokemon, so they're all about 7~ levels higher than mine! The exp boost you get from max Aime love is pretty great.