Behold, the Tyrell Corporation’s inferior model Nexus replicants:

Nexus-1 was their Turd Burglar model. All he could do was steal turds out of unsuspecting people’s toilets.

Nexus-2 had the strength and agility of the Nexus-1, and more skills. However, he lacked focus and was very lazy, spending most of his time trying to pick up women and failing.

Nexus-3, lacked the empathy of previous model replicants. He was built to stay on task and had good focus. However, he gained too much weight from eating burgers and fries at the Los Angeles In-and-Out Burger joints and had to be be retired.