This was confirmed by MTGs Lead Designer, Mark Rosewater, following a question from Tumblr user Jonpaulcardenas
Corpseberry Cultivator While its nice that Corpseberry Cultivator has a lot of growth potential, you specifically need to forage to get there
You are greeted with the entirety of your collection sorted in color order
the player is affected by spells and abilities that do not target them (every player..., all opponents..., etc.) and do not deals damage to him
Not only does it have impressive stats and keywords for its cost, it allows all of your squirrels to buff squirrels, and draws you cards when your Squirrels hit your opponent
A few cards like Zulaport Cutthroat and Corpse Knight help your creatures deal damage when they die or come into play to get those last points of damage through