Denseri, Keeper of Wild Lore

Whenever a land card is put into your graveyard from the battlefield, create a 2/2 green Bear Druid creature token. It has "{t}: add {g}"
{x}{g}, {t}: Search you library for a green creature card with converted mana cost X or less, put it onto the battlefield, then shuffle your library. Spend only mana from creatures to activate this ability.
"Come, cubs, and learn."