Warning: This post contains major plot points from the third season of13 Reasons Why.
DO NOT READ unless you want to have the season’s mystery spoiled for you.
A fight broke out.

Credit: David Moir/Netflix
Zach was carried off the field with a busted knee.
Everyone else walked away with black eyes and bruises.
But Bryce walked away never to be seen again.
At least not by everyone.
And before we reveal the answer, let us once again say this: THIS IS A MAJOR SPOILER.
Only scroll if you want all the answers…
…
He had something he wanted to give to her.
There, Zach fought Bryce, breaking one of his legs and one of his arms in the process.
But Zach didn’t kill Bryce.
He simply left him with no way to get home (or even get up).
After Zach left, Jessica and Alex showed up.
(She brought Alex for protection.)
But just as Jess and Alex started to leave, Bryce asked if they could help him get up.
At that moment, Alex shoved him into the water where Bryce would go on to drown.
And yet, Alex didn’t go to jail for his crime.
So not only did Alex kill Bryce, but he got away with it.