Bellerophon

Brave. Bellerophon has advantage on saving throws against being frightened.

Spellcasting. Bellerophon is a 3th-level spellcaster. Its spellcasting ability is Charisma (spell save DC 12, +4 to hit with spell attacks). He has the following spells prepared:

Cantrips (at will): thorn whip

1st level (4 slots):  armor of agathyst, ensnaring strike, entangle, longstrider

2nd level (2 slots): barkskin, earthbind

Born to saddle. Bellerophon has advantage on saving throws made to avoid falling off his mount. If he falls off his mount and descends no more than 10 feet, he can land on his feet and is not incapacitated. 

Finally, mounting or dismounting a creature costs him only 5 feet of movement, rather than half his speed.

Multiattack. Bellerophon makes two melee attacks.

Spear. Melee Weapon Attack: +5 to hit, reach 10 ft., one target. Hit: 7 (1d6 + 3) slashing damage.

Leadership (Recharges after a Short or Long Rest). For 1 minute, Bellerophon can utter a special command or warning whenever a nonhostile creature that it can see within 30 feet of it makes an attack roll or a saving throw. The creature can add a d4 to its roll provided it can hear and understand the knight. A creature can benefit from only one Leadership die at a time. This effect ends if the knight is incapacitated.

Protection. Bellerophon adds 2 to an ally AC against one attack that would hit it. To do so, Bellerophon must see the attacker and the ally and be wielding a melee weapon and/or shield.