That it Gurgox you talk of. And he does do a growl before he uses his wipe move, last time I checked. Is your game sounds on in options? Device volume up too? A few other bosses have special moves, and they have some kind of warning just before it. Aunt Emma for example in Fang and BSM has a super pulse kinda thing that she does every 15 seconds or so. Before it happens she skips one of her regular damage pulses and there is a pause, then the big pulse comes.