Ghoulsteed

Pounce. If the ghoulsteed moves at least 20 feet straight toward a creature and then hits it with a bite attack on the same turn, that target must succeed on a DC 14 Strength saving throw or be knocked prone. If the target is prone, the ghoulsteed can make one bite attack against it as a bonus action.

Sprint (3/Day). When the ghoulsteed uses the Dash action, it can Dash again as a bonus action.

Undead Fortitude. If damage reduces the ghoulsteed to 0 hp, it makes a Constitution saving throw with a DC of 5 + the damage taken, unless the damage is radiant or from a critical hit. On a success, the ghoulsteed drops to 1 hp instead.

Multiattack. A ghoulsteed makes two bite attacks.

Bite. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 13 (2d8 + 4) piercing damage and the ghoulsteed gains 5 (1d10) temporary hp. These temporary hp stack with each other, but the ghoulsteed can only have a maximum of 10 temporary hp at one time.