Board Thread:General Discussion/@comment-26366000-20150601133703/@comment-34280301-20180201010622

In my opinion, the best strategy to deal with Plantera is to use a large circular arena with another circular object in the center for the first form and a very deep bottom. From what I have seen, however, is that this strategy is mainly ineffective in the second form, as she/he is simply too fast to try to avoid using a circle. Because of this annoying fact, I used to get stuck on Plantera and think she was one of the "hardest" bosses in the game.

However, I discovered by accident that Plantera is very slow going downwards in her second form, and decided to make a deep, straight, 5 block wide tunnel for the second form. This worked beautifully. since she shoots no projectiles, and moves slowly, I could practically just glide down to the bottom while bombarding her with a meteor staff.

This is a great strategy if you've mastered dodging her in her first form and are having trouble with how "big" she becomes in her second form.

-Hope I helped!