You opponent allocates wounds only after your entire unit has completed all of its attacks. So in your example, they couldn't remove those models to avoid the Dracoth's attacks because rider and mount are in the same unit so casualty removal doesn't kick in until both of them have fought.
Note that this is how each attack sequence is resolved. If an ability lets a unit pile in and attack twice in a single combat phase, they're resolved totally separately, so your opponent could try some casualty removal shenanigans before your second go round. Similarly, another unit attacking in the same phase could be cleverly stranded by picking allocating wounds closest to them. But that's what pile in moves are for!
So no, basically. Page 7 of the AoS rule sheet covers the procedure for allocating wounds.
|