20.     Studies — the beauty of chess composition
This collection of interactive puzzles aims to introduce the concept of a chess study and demonstrate how beautiful chess can be in spite of a limited number of chessmen. A study is a composed puzzle where White is supposed to achieve a win or a draw by making the only right moves. The solution of such a puzzle consists in playing out all the significant moves for both sides until the result becomes obvious in light of well-researched endgame theory. Studies are composed so that each conceptually different defensive line for Black is answered by a different concept in White’s play.

21.     Studies — selected teams of chessmen
A collection of endgame studies grouped according to the team of chessmen cooperating to achieve the stipulated goal: win or draw. These exercises serve to practice the effectiveness of cooperation between various teams of chessmen: rook and king, two rooks, queen and king, bishop with pawns, knight with pawns, rook with pawns, queen with pawns, pawns and the king, bishop pair with pawns, two knights with pawns, bishop and knight with pawns, queen and rook with pawns, rook and bishop, rook and knight, queen and bishop, queen and knight.

22.     Studies — various numbers of chessmen
A collection of studies grouped according to the number of chessmen on the board. Each time at least three White pieces cooperate.