"Normal" people can't see in the dark, live for multiple centuries, cast spells, turn undead, throw a "flurry" of kicks and punches, defeat gravity with a tumble-check, take more physical damage than a Tyranosauros Rex or any number of other things ...Turning into a bear is considered "cheating". Normal people do not turn into bears.
... but people in Faerun can!
Regardless, by the time we get to the end of this competition, one fighter will be heavily favored over the challenger, but that heavily favored fighter is going to suffer an shocking upset.
*****
In a dimly lit tavern not far from Skullport's fighting arena, Aliyah sits across a table from Bu.
"In the fifth," Aliyah says, "your ass goes down. Say it."
Bu looks at her emotionlessly across the table. "In the fifth, my ass goes down."
Aliyah stares back at him. "You see, this profession is filled to the brim with unrealistic motherfuckers. Motherfuckers who thought their ass would age like wine. If you mean it turns to vinegar, it does. If you mean it gets better with age, it don't."
"But, uh, in D&D we DO get better with time," Bu improvised off script, "we go up in levels, get more hitpoints, better bonuses, more spells, I mean, hell, by the time most people are ready to retire we are veritble gods of ..."
"The night of the fight," Aliyah interuppted, "you may feel a slight sting. That's pride fucking with you. Fuck pride. Pride only hurts, it never helps."
"But ..."
"Cut, cut already, thats a wrap."
cue music ...