Back in 2007 – 2008 I produced a game type I still dream of completing to this day. A sort of Castlevania meets Shadow Of The Beast platform game with painterly pixel graphics, branching paths and fast action.
I used Power Game Factory, an engine and editor suite designed for making platform games for PPC Macs. Scripting in PGF is visual, but things like AI and physics are often quite complex to set up. I would spend many hundreds (thousands?) of hours drawing sprites, backdrops, composing music and setting up the gameplay.