In the meantime, Lazav is eating that Atraxa, Grand Unifier out of the opponents graveyard on turn 3, and maybe even as a 7/7 lifelinking flyer
Yes, a creature can grow for hitting a player, but having a toughness boost while there is damage being calculated is just confusing
The real power, however, lies in the Sneak mechanic
These cards are the glue that hold modern midrange decks together because of their insane flexibility
A bounce land like Simic Growth Chamber can help reduce your land count without sacrificing any mana development
While the Plains count effectively time gates its effectiveness, youre usually going to be able to get rid of what you need to if you build your mana base properly especially given all of the new ways to grab Plains, like Archaeomancers Map