I'm looking at this mechanic in two separate ways - the first is strictly top down. You place a bounty, and when the creature dies, you receive the reward for that bounty.
County Sheriff - 2W
Bounty - When ~ enters the battlefield, place a bounty on target Creature. When that creature dies gain life equal to its toughness.
2/3
The other way to look at Bounty is as the opposite of Soulbond - allowing for negative effects instead of positive. You can either keep the death trigger or make it a static effect.
Alternative wording - You may pair this creature with another unpaired creature an opponent controls when either enters the battlefield. They remain paired until one leaves the battlefield.
El Torturador A - 2BB
Bounty - (You may pair this creature with another unpaired creature an opponent controls when either enters the battlefield. They remain paired until one leaves the battlefield.)
As long as El Torturador is paired with another creature, that creature gets -2/-2.
3/3
or
El Torturador B - 2BB
Bounty - (You may pair this creature with another unpaired creature an opponent controls when either enters the battlefield. They remain paired until one leaves the battlefield.)
Whenever a creature ~ is paired with dies, target creature gets -2/-2.
3/3