Thank you for the feedback!
3 levels were reuploaded after adjustments. I'm aiming for "classic Mario" feeling on most of them so I'm glad that shines through!
You're right about the downwards climb with magikoopas, it's a critical part of the level. It's unfortunate that one has to rely on luck when trying to make the magikoopas destroy the blocks. Ideally it's only a matter of holding out for a while, but sometimes the rooms get filled with more enemies than intended before you can get out.
The ghost house is a tricky riddle, once you figure it out it's an easy passage! All I wanna say is that everything you need to clear it is inside the ghost house