Creature - Plant
GG, Sacrifice a Forest - Regenerate Carniflora.
As hungry for minerals and sunlight as it is for blood.
(May need some tweaking here - a 4 mana 3/3 is rather rubbish although green shouldn't have a problem having spare mana / forests lying around.)
Strategy and Tactics
Carniflora does not have a very good statline, but it can trade repeatedly as long as you have two untapped forests (you can tap the forests for mana before sacrificing.) It's a good answer for sweepers for green as it can help them maintain board state through a board clear.