Since, in those games, the attacking side has twice as many pieces as the defending side, it is commonly assumed that in Alea Evangelii there are 48 attacking pieces and 24 defending pieces. Actually, the manuscript mentions the existence of attackers and defenders, but the two sides are not differentiated on the diagram, which only presents the details of how the pieces are assigned to the four evangelists according to the Christian allegory which is the main subject of the text. In other tafl games the goal of the attacker is to capture the king and the goal of the defender is to make the king escape from the board, it has been assumed that this is the case also with the game on which the Alea Evangelii moralization was based. Games of the tafl family only have two kinds of pieces: a king that occupies the center of the board in the initial layout and a number of ordinary pieces divided between attackers and defenders with a 2:1 ratio. The "dukes and count" that appear in Alea Evangelii do not seem to fit this simple scheme. Mac White notes that CCC MS 122 "mentions dukes and knights, presumably pieces, which is rather puzzling". According to Bayless, "there is no precedent for such an elaborate distinction of pieces in other games played in Anglo-Saxon England, and the archaeological record shows no evidence of such pieces. It is tempting to suggest that on his travels, perhaps in Rome, Israel may have heard of the new game just beginning to circulate in Europe, chess, with its comites, milites, and other pieces, and borrowed the idea of different ranks from that game". While all other scholars have assumed that the game is played on a 19x19 board, Barbet-Massin's opinion is that the external lines of the board do not make part of the playing area, so that the actual size of the board is 17x17.