The hint / FIXME define the data for the move in the game / could be made more clear. Use “initialize” instead of “define”. I assumed it was to define new derived datatypes.
For me making a reference to Pokemon made the exercises go out of context.
Day 2:
Choose a linear color gradient for the All-to-all visual
Add FIXME in the exercise scaffolds so that editors highlight it.
Maybe go deeper into the halos/border problem. Or a N-body problem for classical Molecular Dynamics and show the advantage of using non-blocking.
Day 3:
The visuals in third episode (synchronization) could be improved with some arrow heads. Also, the lines in the visuals have new colours (red, green & purple) which is different from the previous two episodes (red and blue).
Day 1:
Day 2:
Day 3: