Super Mario Bros. X Forums

I've seen levels in which there's a star coin hud, which increments itself as you collect star coins, but I never learned how to do it myself

So how can I do it? Does it require luna.lua?

this is a vanilla feature of SMBX2. all you need to do is set the index of each star coin inside the level. the index should start from 1 and increment by 1 for each star coin, and you also have to make sure you're using the lvlx format (otherwise the settings won't save).