Our createMario function have been asynchronous for too long! In this episode I demonstrate the drawback with that and we rewrite our entity creation to be synchronous and add Goombas and Koopas.
Since we are writing modern JS this code might not run on all browsers yet. I was running Chrome 61 when I wrote this and if you wish to follow I recommend you do too.
Source code with step-by-step commits:
Demoscene Time Machine