As a single creature that provides a threat, ramp, and card advantage in one, its terrifying to face down in the command zone
It's not until the starting player begins their 3rd turn that things get interesting
The size of these combined with vigilance means theyre always a threat, and if you happen to have this and Diregraf Colossus out then youll likely be getting three Zombies per Zombie, and thats just pure value
Usually, the red/black deck either blows its hand and starts top-decking or it has to rely on its black side to spend life to draw cards
Heres a rough outline of the decks that Id build (or like to see built) with each of them
Of the Simba cards in The First Chapter, Simba, Returned King stands out