Champions are not a key part of the Storm Goblins and serve more as auxiliary tools. The faction acknowledges this by making all three champions cost only 4 magic, allowing them to fit seamlessly into the Goblins’ strategy without disrupting their magic economy.
Brakka is the simplest of the three champions to use. Essentially a larger and faster Gust Strider. While it lacks Tireless, but makes up for it with increased speed making it a significant threat to enemy Summoners, and its extra damage is excellent for pairing with Chain Lightning. However, unless you need the extra movement speed or damage to handle a 4-health target, Gust Striders are generally more efficient. Still, the 4-move speed of Brakka makes it a massive threat in a faction that excels at poking Summoners.