Engqvist - 300 Most Important Chess exercises

The 300 exercises on offer are presented as follows: 150 exercises on the beginning and middle of games (75 on tactics and 75 on positional play) and a further 150 exercises on the end of games (again half and half on positional finishes and on tactics in the final).

The author had already proposed others in the same genre, such as this one and this one.