Forest stalker provides speed and attack
This mod enables the wood elves to get increased movement speed and attack in forests (20% bonus each), making the forests excellent area’s to fall back through or pull enemies in, as all your units become excellent mobile hit and run units.
I did however remove all the other "buffs" including the defence (15%) and accuracy (50%) buff, as I felt they didn’t really fit with the wood elf theme and felt extremely lame.
Is it overpowered?
Absolutely not, as it encourages the player to use movement to his advantage, which is a unique and complex mechanic that is only effective if the player knows how to isolate units and perform hit and run attacks. Or, you know, skirmish the enemy with missile units at close range where the trees barely block their shots.