A: Almost every single game in Pyramid Arcade can be played with 2 players. Only a couple are probably still better with more (or less!), and many are 2-player only.
1-2 or more:
Color Wheel is perhaps best viewed as a solitaire game, but it’s fun to play cooperatively with two, or you can play it competitively by seeing who can solve it in the fewest moves.
2 player only:
2 or more, absolutely fine with 2
Volcano (actually better w/ 2 than more)
2 or more, but better with more
Give or Take
World War 5
more than 2
Pyramid-sham-bo (listed in the book as ok for 2, but that’s a typo. Actually really the more the merrier.)