Enigma vs Viper

How this matchup plays

Thinking Viper's kit automatically shuts down Enigma can be a trap. While Nethertoxin's break is effective against Eidolons, landing it on Enigma himself before he channels Black Hole is very difficult. A successful Blink Dagger initiation from the fog gives Viper almost no time to react and place his spells. Corrosive Skin might deter Eidolons from focusing Viper, but it’s irrelevant against the lockdown from a good ultimate. Viper has the right tools in theory, but Enigma's instant teamfight presence often lets him act before those tools can be used defensively.

This makes late-game fights about which hero sets the tempo. Viper's goal is to stay on the edge of the fight, using his slows and Nethertoxin to make the battlefield dangerous for Enigma to enter. If he can get Viper Strike on Enigma early, the initiation is often completely neutralized. But Enigma’s team will be working to find one clean opening. If they get the jump, Viper has no escape or way to interrupt a Black Hole. He dies as easily as any other hero caught inside, making the entire engagement a coin flip based on who gets their ideal setup first.