I have changed the abilities and some stats of the cards.
Dryad/ Elite Dryad:
* increased the cost from 4 to 5
* decreased the attack from 3 to 1 for the Dryad and 2 for the Elite Dryad
* the ability heals 1HP per Dryad
The question is if the healing should increase with more Dryads on the field.Oak Guardian/ Oak Warrior:
* removed ability Symbiosis, the HP of the both creatures is 7
* decreased the cost of Oak Warrior from 9 to 8
* grammatical correction