That was a fun experience. I just completed the game in ~75 minutes with 777/777 coins but I only got the normal ending. Looks like I'm missing one gem. Is there a quick way to know in what zone to look or do I need to backtrack everywhere to find it? I'm pretty sure I'm only missing one. Regardless, it was a lot of fun and I enjoyed the challenge near the end. Thanks!
Edit: I've just found a full map online and I'm now 100% positive I got all gems. Also, they're all surrounded by coins so it's hard to get 777 coins and not all gems. Unless I'm really missing something? hahaha ! Anyway, it was great fun. Congrats for your game!
Edit 2: Oh... I think I've seen something on the map I was missing... don't want to write spoilers here for other thought...
I'm glad you enjoyed it!
It sounds like you figured out how to get the Secret Ending, and that it involves finding a different way to leave the island instead of the door on the airship, I hope!
(If not, there was a hint in the Normal Ending text).
Thank you for leaving such kind comments!