Anaconda Virtue is a powerful character with 3 phases, which involve him running to several different areas in the Red City. Known as the "Hottest Snake in the Franchise", Anaconda can shoot fire from his hands and spit oil at his foes, making him a tough opponent. Thankfully, many Man-Made Salts can be found before encountering his fire-throwing phases. His corpse can be taken to Lester for an award, and you can also find a Save Crow and a Condition Killer if you go on after you defeat him.
Do not try to finish off Anaconda in the first two phases as you'll basically be wasting bottles/SP. however it's still possible to defeat him in those two phases, by lowering his health between 850-900 and then using a joyed minor iris in a wary Anaconda, leading to this piece of dialogue in both defeated phases: "You know, I'm not even mad".
In his final phase, he starts off with Choirboy's Screech, a move that reduces both Alex and Joel's SP by 40, and makes them cry. He also does it again when he has very little health remaining.
As of 1.3.0, Anaconda has a fourth phase, encountered when his third phase has 30% HP or below.