Thank you to everyone who participated in this as well as Parallel Universe 3. The last 2 installments were a challenge from the perspective of coming up with ideas that work interestingly within the respective themes and I'm generally happy with how things turned out and I am glad that people seem to have enjoyed the contests in general.
Congratulations to the winners. The top 3 have been the same across both contests, with just a swap between 2nd and 3rd places, which shows that these solvers are skilled at sprint solving as well as solving tougher puzzles. Really impressive performances.
Thank you to Rakesh, Murat, Philipp for their help with putting this together, and of course to Swaroop for his continued work on improving penpa-edit.