It's not really suicide. They disappear because one bite per sleg is enough, and to prevent areas with Handlers from turning into one writhing, homogeneous ocean of sleg.
Sill, I would have preferred to see slogs, or slogs and slegs. Perhaps strategically distributed to help emphasize the change in environments, and to connect the game to the previous ones more. I know OWI wanted new characters to keep the continuity somewhat separate from those we loved, but a few more lowest-of-the-low animals like slogs, even fleeches, would not in my opinion, have damages that goal and actually enhanced the Oddworld experience of Stranger's Wrath.
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