Gladiator

A gladiator on the party's side is hired muscle, a former opponent the party defeated and then drank with, an arena champion paying off a debt of honor, or the bodyguard a noble assigned to them and who turned out to be more loyal than the noble. CR 5 puts this companion in the sweet spot for a party of 3 to 6: real combat output without overshadowing a PC fighter. Treat the gladiator as a colleague, not a follower, and let them disagree with the party's plans out loud.

In a fight the gladiator is a frontline anchor with thrown reach. Open with a javelin at the enemy spellcaster, then close to engage the heaviest melee threat the party doesn't want chewing on the cleric. Multiattack is three Spear strikes with the option to swap in Shield Bash, which means the gladiator can knock a key enemy prone for the rogue's sneak attack the following turn. Coordinate that. Players love the moment the NPC sets up the player's big swing. Parry holds for the moment a serious hit lands on the gladiator themselves, since 112 HP is a lot but not unlimited.

The gladiator refuses three things. They do not kill children. They do not break a written contract, even one the party thinks is unjust. And they will not fight against their own house or arena unless the party gives them a reason that holds up in their own moral framework. Build at least one of these into the campaign so the players have to navigate it.

Have the gladiator name a price for their service before the first job, and have them honor that price exactly. No upselling, no hidden fees. The reliability is the character.

A gladiator is the SRD's stand-in for any trained human melee threat: arena champion, bodyguard captain, traveling duelist, the sheriff's enforcer in a frontier town. CR 5, AC 16, 112 HP, three Spear attacks per Multiattack at +7 for 11 piercing each, plus the option to swap one attack for Shield Bash (DC 15 Strength save, 9 bludgeoning and Prone on a fail for Medium or smaller). The Parry reaction adds 3 to AC against a single melee attack. Run this as a duelist who reads the room.

Open with the spear thrown. The Spear stat line covers ranged 20/60 ft. as well as melee, and the gladiator carries three. A first-round javelin into the squishiest target before closing distance is the move, both for damage and for table feel: this is a person who knows how to open a fight. Once in melee, the standard turn is two Spear attacks plus Shield Bash on the front-line PC most likely to fall over. Prone gives the gladiator's allies advantage on the next attack and forces the prone PC to spend half their movement standing, which is a real tax on action economy. Save Parry for the crit or the high-damage attack you can see coming, not the first to-hit roll on the round.

The gladiator does not have spell resistance, dark vision, or any save proficiencies that protect them from save-or-suck. A successful Hold Person ends the fight. Play this fact honestly. A smart gladiator carries iron filings or a small shrine token and tries to break concentration on the wizard between Multiattacks. If they have backup (which they often will, since gladiators are rarely solo), the gladiator marks the caster on round one and the rest of the team flanks them.

Gladiators surrender. They are professionals, not zealots. Once Bloodied with no allies standing, the gladiator drops the spear, kneels, and asks the party's terms. Have a price ready: the name of who hired them, a contract on a folded paper, the location of the back door out of the arena. Mercy buys the campaign more than another body on the floor.