I tried out an Ice40 version of Space Invaders on the TinyFPGA BX. This uses a 36Mhz clock to drive the VGA monitor at 85hz.
I noticed from another fork of the repository that @juanmard got there first with a port to the Alhambra board.
I think this version of Space Invaders needs a bit of work on it. There is no sound yet and the shoot button doesn’t seem to work consistently, but that could just be my lack of skill or bad wiring.