If you're still playing Red Dead Redemption online, or still want to hit level 50, the servers have been hacked, but in a good way. Somehow, when you spawn generally in MacFarlane's Ranch there will be NPC's sprawled out on the ground, dying. If you shoot one, the game will go into a weird "turbo" mode, and you'll get 1xp per second per NPC you shoot. You might get a wanted level, but once you lose it it won't come back. Just stay in the vicinity of the NPC's and you'll rack up XP quick.
I went from 17 - 50 in less than an hour, and that's with getting killed a couple of times.
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