Think About the Map
The 1v1 elimination mode used to place you on the same map every time. After all, there was only one map available for these kinds of brawls. Now, however, there are four different locations where you may find yourself trying to take down one lone opponent. This is important to keep in mind as this can change the dynamic of character matchups. Each of the new maps present very different landscapes and different environmental elements that can play into your strategy. Sometimes the real question isn’t which character can deliver the most damage or who has the stronger defenses. It may come down to whether or not a certain type of map has left certain heroes with less impactful kits.
A map like Castillo presents far too many different routes that players can use to get behind their enemy while remaining undetected. That means a shield won’t really do much good here and a sniper could find themselves in trouble if the enemy suddenly pops up in close range. Considering your environment when selecting your hero and then capitalizing on different elements of the map will be (and always have been) key to dominating one-on-one battles.