Map of ancient forest you have three slots available to add common towers and this is fantastic as you have availability to use different towers and to get a better results in any map as you can see that I have 3 common ones.
Common towers is not such bad as you have to use them well to get your best results and I have 3 ones that are so effective and good in this battle.
First one is Gloom Owl and as you know that tower is a very good one to attack most types of fiends and the best thing about it is attacking flying ones.