The rulebook isn't all that clear on the timing of both of those Vuko special tiles. When does Vuko move the dead snow marker once Both bears is active? During his activation? At the end of the turn? During the initiative phase? Also when does Nightwalkers trigger? I.e. if Vuko enters a region and gives a Vuko-marker to one of the players present, does Nightwalkers immediately trigger? Or just before handing out new Vuko-markers?