Pets shouldn't do damage to players—the Elise problem.
Late game, if Elise gets her ult off just as a match ends and each unit is—for example—doing 4 damage and she's a 3 star, she's doing 20 damage to players. A 1-cost unit doing extra damage to players is intense and questionable already, but she does A MAXIMUM OF FIVE TIMES extra player damage. This can make you take 25+ damage late game if you get stomped in one fight just from Elise.