Cultivators Caravan could be a part of some four- or five-color midrange, ramp, or control strategy, assuming you have some passable bodies for crewing it
Having the copy ability on the Commander is extremely powerful, and having copies of Unicorns, Horses, and Pegasi running around is very strong
Liliana offers the ability to pump up a board with 2/2 Zombies, giving a player plenty of blockers to throw under an attack, and subsequently letting them draw a card
Two mana for 3 damage at instant speed is the gold standard on its own, so if you can find both colors of mana regularly this is like starting the average game at 22 or so if you can pack four copies
That means they arent killed in regular combat
To show how efficient this card is for the right deck, the final versions of Miracle Grow, which were dubbed Super Grow, used Mystic Enforcer as a finisher, since by the time you'd get around to casting it you had an all but guaranteed 6/6 flyer for four mana