Oberon, traditionally associated with order in A Midsummer Night's Dream, causes chaotic activity in this act. He has given Puck instructions to anoint the youth wearing "the Athenian garment"; however, Puck mistakenly anoints the eyes of Lysander with the love portion, instead of those of Demetrius. When Lysander opens his eyes, then, he falls in love with Helen who has awakened him after entering the woods in pursuit of Demetrius. With the potion on his eyes, Lysander falls in love with Helen, but she believes that he mocks her as he speaks of his regret about loving Hermia.
When Lysander does see Hermia, he no longer loves her; he loathes her. The arguing of Oberon and Titania has caused the natural world to be at odds with itself. In his efforts to control Titania and bring peace to his marriage, which will effect a settling down of Nature, Puck's mistake causes more unrest.
Oberon plans to take the changeling child of Titania while she is under the spell of love. However, Oberon is unaware that Bottom has entered the forest to practice a play with the other mechanicals. An observer of their bungled practice is Puck, who turns Bottom's head into the head of an ass. After this trick, Titania awakens, and looks first at Bottom, falling in love with the man who has the donkey's head.
What follows is hilarious as Bottom, unaware of his changed head, he accepts his position as lover to the fairy queen when she tells him "I love thee":
methinks, mistress, you should have little reason
for that; and yet, to say the truth, reason and love keep
little company together now-a-days; the more the pity,
that some hones neighbours will not make them friends.
Nay, I can gleek upon occasion. (3.1.134)
Bottom banters with the other fairies, a comical scene, indeed, as a man whose head looks like that of a donkey criticizes others.
Oberon, king of the fairies, wants a certain orphan boy to be his page, but his wife, Titania doesn’t think it’s a good idea. Therefore, he asks one of his underlings, Puck, to bring him one of Cupid’s magic flowers, which have the power to cause people to fall in love. His plan is place the enchanted flower on Titania’s pillow in the hope that she will fall in love with a monster and leave him free to do as he pleases. However, a group of actors is also rehearsing a play in the forest. Puck amuses himself by using magic to give one of the actors a donkey’s head. Unfortunately, this actor is the first person Titania sees after being exposed to Cupid’s flower and she falls deeply in love with him. Oberon is amused, but eventually the couple reconcile.
As Titania does not give the Indian boy to Oberon, he gets furious and orders Puck to pour the juice of a magical flower, idleness, nowa days known as a love potion. He drops the juice onto the eye lids of Titania to make her fall in love with the first thing she sees, which can be anything, Then she will beg Oberon for solution of this shameful love potion she is bined to.