Reach
{3}{G}{G}: Create a 3/3 green Beast creature token.
{3}{G}{G}, Exile Soul of Zendikar from your graveyard: Create a 3/3 green Beast creature token.
Exiling the Soul from your graveyard is part of the last ability’s activation cost. A player can’t remove the Soul in response to prevent you from activating the ability.
You can activate the last ability only if the Soul is in your graveyard.