This is similar to Egg's idea about daily quest, but how this works is that you put a quantity of money on someone's head and then people will try to claim that bounty (the same as how GTA 5 has the bounty system). It is essentially a player making "quests" of their own without the developers making them.
Initiate bounty on someone's death + Reward( 500 coins minimal to discourage players abusing this mechanic. Also the player with a bounty on his head can't kill himself to claim the reward ) = MANHUNT
Hunt who you want. Friends, strangers, etc.
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