At a distance, this beast appears to be an armored warhorse but upon closer inspection its true nature becomes clear; it is a foul amalgamation of equine and insect. Chocolate-brown chitin covers its head, neck, and flanks. Its rear half is closer to a thin beetle’s abdomen and thrums with electricity. In place of a mane there is a line of fine antenna writhing atop a thundercharger’s neck. Its segmented gaze is cold and hungry.

Unflappable. Thunderchargers are not prone to panic, or too much emotion at all. They are driven by simple desires: to feed, mate, and please their masters. This makes them well suited to work with the nobles of the waning court given the crashing thunder and bolts of lightning cast-off by the fey host. Even the presence of an angry dragon doesn’t rattle these steeds, though it might unnerve the fey riding them.

Thundercharger

Large monstrosity, unaligned

Armor Class 16 (natural armor)

Hit Points 68 (8d10 + 24)

Speed 40ft

Str 20 Dex 12 Con 16 Int 6 Wis 12 Cha 8

Condition Immunities blinded, deafened, frightened

Damage Immunities ligthtning

Damage Resistances thunder

Senses tremorsense 30ft, darkvision 120ft, passive Perception 11

Languages understands sylvan, but cannot speak.

Challenge 3 (700 XP)

Trampling Charge:

If the thundercharger moves at least 20 ft straight toward a creature and then hits it with its stomp attack on the same turn, that target must succeed on a DC 15 Strength saving throw or be knocked prone. If the target is prone, the charger can make another attack with its stomp attack against it as a bonus action.

Actions

Stomp:

Melee Weapon Attack: +7 to hit, reach 5ft., one target. Hit: 12 (2d6+5) bludgeoning damage plus 9 (2d8) lightning damage

Booming Gallop (Recharge 6):

The thundercharger and its rider(s) teleport up to 90ft. Each creature within 10ft of the space the charger left must make a DC 13 Constitution save or take 11 (2d10) thunder damage. Creatures take half damage on a successful save.