ATK swarm is a common, and typically very hard to balance mechanic.
In its current state, this card will likely invite massive fractal abuse.
It you may be able to get it to balance if you constrain the growth rate somehow. E.g. limit to creatures in the same row or something.
If you're going with a wolf theme, this might be useful for art (its the alpha wolf art I made for openEtG):
![](http://i.imgur.com/KKJBjwW.png)