Consider passing bone 0 in cards invalid.
?^ -.q.vax :_(+>.$ [%| (ap-suck "move: invalid move (bone)")])
?@ +.q.vax :_(+>.$ [%| (ap-suck "move: invalid move (card)")])
=+ hun=(~(get by r.zam) -.q.vax)
- ?. (~(has by r.zam) -.q.vax)
+ ?. &((~(has by r.zam) -.q.vax) !=(0 -.q.vax))
:_(+>.$ [%| (ap-suck "move: invalid card (bone {<-.q.vax>})")])
=^ pec vel (~(spot wa vel) 3 vax)
=^ cav vel (~(slot wa vel) 3 pec)
