Master of All Weapons
A gladiator often has to improvise with the weapons he/she is given in the arena.
Beginning when you choose this archetype at 3rd level, you gain proficiency with improvised weapons and your unarmed attack deals 1d4 damage. (See page 147 PHB for the improvised weapon rules). A broken weapon counts as 1d4 damage and it is broken a second time it is completely unusable and cannot be repaired.
Starting at 7th level you are well practiced with working with others in combat. Also he/she has learned how to work the crowd in and out of the Arena.
You can take a bonus action to use the Help action. Additionally the gladiator gain proficiency in Intimidate and performance skills.
Additional Fighting Style
The gladiator is a master of many different martial styles in order to adapt to new combatants as they climb the ranks of Arena Combat.
At 10th level, you can choose a second option from the Fighting Style class feature.
Gladiators often love to the center of the spotlight or at least have learned how to push their opponents buttons.
At 15th level the Gladiator may five up one of his/her extra attacks in order to force an opponent to focus on them for the next attack. If the target does not include them in at least one attack the attack roll is done so with disadvantage.
We who are about to die salute you
Arena fights can be turned around in the blink of an eye. Often a fight is won by who is more willing to live.
At 18th level a gladiator can pull himself from the brink of death. The gladiator gains a second use of the second wind class feature, but this may only be used when the gladiator has been reduced to 0 hit points and fails to kill the gladiator outright. This version of second wind also recharges after a short or long rest. The hit points are regained before the gladiator falls unconscious.