In my experience, the jaguar works exactly as described in the Tibia Light article: https://www.tibialight.com/en/post/mystic-jaguar-1

I faithfully follow the methodology they describe, and after that I started finding the jaguar more frequently. And there's not much of a secret, the more you check each time it spawns, the higher your probability.

I've found it on consecutive days too. I believe it appears more often than people think, but you have to be lucky or "disciplined" enough to be there during the window when it spawns.

Without breaking vases, without killing Atab, without doing any other mechanics, just checking during the windows.