This card is a boss, not that it looks like it. This is not a card that you run on its own, unless you're playing a really defensive deck. However, with certain cards, this card can be awesome. With Acorn Catapult for example, it makes 2 creatures every turn for 2 mana. Prodigal Sorcerer also works like this too, but cheaper, but it only produces 1 creature instead of 2. With Pestilence, you can make 0/1 tokens for 2 mana, so it isn't as efficient as Acorn Catapult, but it works faster and only once (lest you kill all of your gribblies, unless you want to, like in a Grave Pact deck). There are better versions of this card (namely Ant Queen), but this card can still stand up. Now, it does cost a fair bit in that it costs 3 to put down for a 0/1, but in the right deck it shouldn't matter too much.
Pros: Highly effective gribblie-producer
Cons: Really hard to get started on its own, a tad expensive