When used, the Brawler charges, then launches forward with their feet ablaze, damaging and knocking back the first enemy hit, while causing the Brawler to bounce back afterwards. This move is similar to Pikachu's Skull Bash and Luigi's Green Missile, in that it can aid the Mii Brawler in recovering horizontally, due to not leaving them helpless and being able to sweetspot ledges. If the move is performed like a smash attack, it charges faster. Another property that the move has include its ability to block projectiles (including King Dedede's Gordos if timed properly). However, when the Mii is in mid-launch, the move can be exploited like any other projectile, and is thus susceptible to Reflectors, which can sometimes cost the player a stock.
Despite the backward bounce upon hitting a foe preventing the attack from being punished with a shield grab, it is still generally unsafe due to its long lag making it easy to hit the Brawler out of it, as well as the bounce still leaving them vulnerable to any other out of shield options such as an aerial attack. As such, Onslaught is often preferred over this move and Headache Maker due to its faster startup and ability to tech-chase. On the other hand, though, the backward bounce does allow the Brawler to evade particularly laggy counterattacks (such as Shulk's Vision).
In Ultimate, the move works the exact same as before, but was heavily nerfed: the move lost its ability to charge and now only deals a set amount of damage because of this, thus hindering the move's horizontal recovery and mindgame potential. However, the move's landing lag can be reduced if used at the peak of a jump.
Special Move customization was added in Super Smash Bros. 4. These are the variations: