Viper vs Io

How this matchup plays

Getting slowed to a crawl by Viper Strike is often the start of a bad fight. With Io on the other team, however, that lockdown becomes much less certain. The movement speed from Tether directly opposes Viper's slowing effects, often allowing a targeted ally to escape what would otherwise be a guaranteed kill. The sustained healing also helps mitigate the corrosive damage Viper relies on to wear down his targets. Viper wants to isolate and melt one hero, while Io's entire purpose is to prevent exactly that.

Throughout the game, this dynamic tends to create a stalemate between them. A Viper player will find it very difficult to secure pickoffs on anyone Io is positioned to save, sometimes forcing Viper Strike onto a less ideal target or having its impact nullified completely. In turn, Io doesn't really threaten Viper and is forced into a purely reactive and defensive role in their interactions. The end result is that they tend to cancel each other out, leaving the game to be decided by how the other heroes on each team perform.