What would happen to the dwarf planet Pluto if all its moons collided with it except Charon?

Depending on how they collide,either the mass of the moons would be combined with Pluto, or there would be a massive ejection of matter away from the surface, some of which could escape the Pluto-Charon gravity and become asteroids or meteors, and some would become an orbiting debris field.

It would not alter the atmosphere, except there would be a lot of dust in the air. I imagine its appearance would be a lot lumpier looking than at present.

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