Website: https://capturetheflag.withgoogle.com/# ... e-minetest
License: Apache 2.0
Download: https://minetest.rubenwardy.com/googlectf2019.zip

There is a gigantic mesecons logical circuit which you need to solve.


Source: liveoverflow.com
Videos and Write Ups
Here are some videos and write-ups which explain the problem and the solution- LiveOverflow (youtube) (blog)
- Team LeaveCat-PLUS (hackmd.io)