A Beauty Cold and Austere

ABCaA is an incredibly polished game, with complex mechanics that perfectly work and some good writing. Its major "flaw" is that it requires too much knowledge from outside of the game. The 4 stars are an average between these two contexts: 1) you are not into mathematics and want a game whose puzzles can be solved "from the inside": 3/5 because the game is very, very strong in many aspects but you shall eventually never finish it; 2) you like maths and are good at them: 5/5, because the game is a romp which is frankly perfect.