Wargames can help you to learn and practice security concepts through games - https://news.ycombinator.com/item?id=29724594 - Dec 2021 (26 comments)

The Bandit Wargame - https://news.ycombinator.com/item?id=29708304 - Dec 2021 (1 comment)

OverTheWire: Wargames to learn and practice security concepts - https://news.ycombinator.com/item?id=16252873 - Jan 2018 (23 comments)

Wargames - https://news.ycombinator.com/item?id=9878302 - July 2015 (17 comments)