Question: where is the circle of slaughter in borderlands 3?
Answer: #1 – Cistern of Slaughter. Location: Promethea, Meridian Metroplex. The first Circle of Slaughter you can find is the “Cistern of Slaughter” in the middle of Meridian Metroplex. ... 
#2 – The Slaughter Shaft. Location: Pandora, Konrad's Hold. ... 
#3 – Slaughterstar 3000. Location: Nekrotafeyo, Side Mission: “Slaughterstar 3000”