So, if you didn't know what sm64 decades later is it's a sm64 remake of the vanilla sm64, Here is the original and here is the coop dx version
The original, if you 100% the game and beat the ztar you get a secret star + a blue star as reward, but if you beat the coop dx version you get a reward star but no blue stars (or blue comets)
The original, if you 100% the game and beat the ztar you get a secret star + a blue star as reward, but if you beat the coop dx version you get a reward star but no blue stars (or blue comets)