draws or revealed checkmate between allies. Alliances Two players may team up against the third, forming an alliance. They may attack each other, but not place each other in check until the third player is defeated, at which point the alliance is annulled. They may not move each other's pieces. Allies may attack each other to gain pieces-in-hand for drops, or to weaken each other in anticipation of the two-player end game. However, if either ally is checkmated by the third player, both lose, so these are dangerous tactics. Forming an alliance An alliance may be entered voluntarily before the start of the game. However, if two players gang up on the third at any time during the game, subject to the following definitions, an alliance is automatically formed. An alliance may not be broken except by defeat of the non-allied player. There are two types of coordinated attack that force an alliance: Discovered attack: One player moves out of the way of a second so that the second threatens the third with "material loss", and Dual attack: Two players in turn make threats of "material loss" against separate pieces of the third player, so that the third player cannot escape both threats. Material loss is defined as any exchange that materially benefits the attacking player. This includes check, threatened checkmate on the next move, threats against undefended pieces (something for nothing), and threats by less valuable (weaker) pieces on defended but more valuable (stronger) pieces (uneven exchange). Possible gain by the third player elsewhere is disregarded, even if this were to make up for the material loss caused by the coordinated attack. Likewise, the sequences of the moves are disregarded, even if they prove the loss of material is more apparent than real. For the purposes of calculating threats of uneven exchange, promoted values are ignored; the ranging pieces rook and bishop are considered equivalent and more valuable than the step movers gold, silver, knight, and the lance, which are in turn considered equivalent and more valuable than a pawn. Finally, check can be considered the extreme case of uneven exchange, so the value scale is K > (R = B) > (G = S = N = L) > p Regardless of whether the situation is a discovered or a dual attack, it does not force an alliance if any attacking move is a direct defense against a