I think there was some talk of Belkar's time being up during the fight with the Bug slavers, and there definately was when the spice-covered Belkar attracted that big worm thing in the desert (to which, I admit, I contributed). Some of this speculation (the giant worm, the arena, the set-up of the fight with Malack) was obviously done deliberately by the author; knowing that two of his main characters have a death prophesy, the author has taken pains to trail/tease the death of the one with the short time limit on that prophesy (i.e. Belkar). Then when the other character who was who was marked for death (Durkon) gets killed first, the surprise/shock is that much greater. Well, that's how it seemed to work on this reader, at any rate!