in a continuation leg ('iso') indicates the length must be the same as the previous riding leg, useful for indicating rifle captures (caibR). Non-final legs of a multi-leg move also have the option to end on an occupied square without disturbing its contents. To indicate this the modifier p is used, and thus has a slightly different meaning than on final legs; the traditional meaning can then be seen as shorthand for paf. To make the a notation more versatile, it can also be used when the moves of the two legs are not exactly congruent: g is an alternative to indicates a non-final leg to an occupied square, but in contrast to p it specifies a 'range toggle', converting a mentioned rider move into the corresponding leaper move (e.g. R ⟷ W) for the next leg, and vice versa (making the traditional g shorthand for gaf). A similar range toggle on reaching an empty square can be indicated by y, to indicate a slider spontaneously turns a corner after starting with a leap. Continuation directions will always be encoded in the 8-fold (K) system, even when the initial leg only had 4-fold symmetry. Mention of an intermediate direction on a 4-fold-symmetrical move would then swap orthogonal moves to the corresponding diagonal moves, (e.g. W ⟷ F) and vice versa. (So mafsW is the xiangqi horse, move to an empty W-square, and continue one F-step at 45 degree, and FyafsF is the gryphon.) Bex notation also adds many extensions for indicating different modes of capture: where a simple c describes replacement capture as in chess, the notations [ca], [cw], [cl] describe capture by approach, withdrawal, leaping over, etc. [crM] describes rifle capture (i.e. annihilating enemy pieces without moving), and specifies with the atom M it contains what can be captured that way. Bex notation also introduces a way to describe exotic effects as a step in a longer move. E.g. [xo] as final move step indicates returning to the square of origin, [xiK] means immobilize all pieces a K step away from the current square, while [x!iK] would similarly mobilize such neighbors. [xwN] would denote a position swap with a piece an N leap away. None of these things can be specified in the original Betza notation, but the downside is that the notations are completely ad-hoc, and do not follow from an underlying principle. Notation used by problemists The