Pen and paper games were quite widespread among Soviet/Russian math olympiad participiants, and sadly these games are practically unknown outside of these circles. Tochki (dots) is probably the most well known, and it even has a Wikipedia article. Klopy (bedbugs) is a much more advanced game, but it's very obscure. The rules were passed orally and probably not written anywhere. It's a multiplayer game, usually for 4 players, which start in each corner of a sheet of squared paper, which is the base (represented by completely filled square). At each turn a player can put a fixed number of "bugs" (represented by X crosses) which can be placed next to a base or your own bug. Instead of placing a bug, you can turn a neighboring enemy bug into your base. I probably don't remember all the rules right now, but that's the gist of it. The games with many players are extremely fun and involve a lot of strategy and diplomacy.<p>[1] <a href="https://en.wikipedia.org/wiki/Dots_(game)" rel="nofollow">https://en.wikipedia.org/wiki/Dots_(game)</a><p>EDIT: I found the Russian wikipedia article for the second game (I was searching for the wrong name): <a href="https://ru.wikipedia.org/wiki/%D0%9A%D0%BB%D0%BE%D0%BF%D0%BE%D0%B4%D0%B0%D0%B2%D0%BA%D0%B0" rel="nofollow">https://ru.wikipedia.org/wiki/%D0%9A%D0%BB%D0%BE%D0%BF%D0%BE...</a> . Looks like I forgot the rule that each base must be "activated" (have at least a single bug next to it) to produce new bugs.