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If some one walked into your local gaming site and had a harlequin army codex list etc etc would you be oppsed to using it ? also what are there pros/cons etc if any one knows ?
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For friendly games, I would allow it, as I am a HUGE fan of Harlequins both fluff and fan-made-rules wise. It really depends on what codex the person is using as far as the pros and cons, but pretty typical of the Harlequins (from GW's pdf rules to fan-made rules) would be their reliance on close combat, and their relative weakness to massed shooting. Don't go throwing yourself into combat with them and lay waste to them with a lot of firepower and you should be set. The only other weakness they have is their expense (typically) - a Harlequin force will have a far smaller number of models than typical forces. Think pure Grey Knights as an example, they are small and elite in a similar fashion.