The correct revision would depend on the context of the sentence, but typically the way "purposes: attracting" is presented suggests it might need a change for clarity.
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If you are listing purposes and "attracting" is one of them, using a comma would be appropriate: purposes, attracting.
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If you are introducing a new sentence that elaborates on the purposes, a period would be appropriate: purposes. Attracting.
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If "attracting" is meant to be a continuation that lists related purposes and should relate to the previous thought, using a semicolon could work: purposes; Attracting.
However, with no additional context, the safest choice to separate ideas clearly would usually be purposes. Attracting.
So, the best option in common usage is: purposes. Attracting.