Bandit's Magic Tachanka

Rapid Fire. Make an amount of spell attacks, up to 3 extra attacks, but for each one roll a d20, and if it goes under the amount of extra attacks, for instance, if you make 3 extra attacks, but roll a 2, the gunner has to make a DC 10+ extra spells used arcane check

Spellcasting. The Tachanka has a large amount of broken wands, spellcasting focuses and a large crystal ball. Its spell casting ability is dexterity (spell save DC 14, +4 to hit with spell attacks). It can make 2 spell attacks without threat of breakdown, but it can make extra attacks with the rapid fire feet.

Roll a D8, and
Cantrips (at will):

1: Magic Stone 1D6 bludgeoning attack

2: A single magic missile 1d4+3 force attack

3: poison spray d12 poison con save

4: ray of frost 1d8 cold attack

5: thorn whip 1d6 piercing, and if the victim is large or smaller it is brought 10 feet closer to the target

6: fire bolt 1d10 fire attack

7: Eldritch blast 1d10 force attack

8: acid splash 1d6 con save acid

The tachanka has 2 actions, one for the gunner and one for the driver

Driver actions:

Dash. Double move speed

Trample. Melee Weapon Attack: +4 to hit, reach 5 ft., 1 target. Hit: # (2d6 + 2) bludgeoning damage. 

Gunner:

Bundle of wands. Roll 2d8, look at the table and use the spells.

Rapid Fire. Make an amount of spell attacks, up to 3 extra attacks, but for each one roll a d20, and if it goes under the amount of extra attacks, for instance, if you make 3 extra attacks, but roll a 2, the gunner has to make a DC 10+ extra spells used arcane check