Easy Mate
It's the Latent Bongcloud line in the Pirc. It's used when white plays a move that seems out of book at move three, causing black to go bonkers and respond with anything similar sounding to bonkers thus borrowing the powerful idea of moving the king a la Bongcloud Attack. 3...Kd7 is in spirit with the Bongcloud even if its sideways.
here is the classical variation
White has many plans after 2.Ke2!! He can choose to exert great pressure on the center with Kd3 or conduct a powerful one man king attack on blacks queenside eg f3 then g4 then h5 then h4 then g3 then g4 then f5 then g6 eyeing the vulnerable f7 square.
funny game