Again, seasonal leaderboards are the answer. Starting everyone from 0 each season would show super fast who is legit and who is dummy farming. It would be far easier for sts to spot those climbing unrealistically fast, (or would be if they gave two hoots about stopping it). It would also give current players a chance at a leaderboard, regardless of level, since those who got their ranks in season 2-4 (and no longer even bother to log in) would no longer be sitting there taking up space.
This goes for all leaderboards, not just pvp.
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