Half-Blue Dragon Gladiator

The half-dragon has advantage on saving throws against being frightened.

A melee weapon deals one extra die of its damage when the half-dragon hits with it (included in the attack).

The half-dragon makes three melee attacks or two ranged attacks.

Melee or Ranged Weapon Attack: +7 to hit, reach 5 ft. and range 20/60 ft., one target. Hit: 11 (2d6 + 4) piercing damage, or 13 (2d8 + 4) piercing damage if used with two hands to make a melee attack.

Melee Weapon Attack: +7 to hit, reach 5 ft., one creature. Hit: 9 (2d4 + 4) bludgeoning damage. If the target is a Medium or smaller creature, it must succeed on a DC 15 Strength saving throw or be knocked prone.

The half-dragon adds 3 to its AC against one melee attack that would hit it. To do so, the gladiator must see the attacker and be wielding a melee weapon.