From the Legend herself

In the past—Forest Settlement.

After Sett killed the boulder-like man with a single punch, as expected, chaos ensued. The people of the settlement began panicking, guards began storming in, and even with all of Sett's abilities as a Tier 4 Tomb Raider and a Tier 2 Axiom Holder, he couldn't fight everyone at once.

After all, there were more than a few Tier 4 Tomb Raiders in this settlement.

Yet, Sett didn't give up and fought valiantly. He tore apart his enemies, healed his own injuries using their slain corpses as fuel, and kept on fighting. His movement, well-trained but untested, became better and better as he kept on fighting. 

But after hours of movement and relentless battle fueled by bloodlust, his inexperienced mind soon became weary.