Dimitri's Flute is one out of three flutes Link receives in Oracle of Seasons and Oracle of Ages. When the flute player blows into the flute in Holodrum and Labrynna, Dimitri the Dodongo will be called.
Oracle of Seasons
Link acquires the Strange Flute when he beats the Subrosian Dance Hall mini-game after gaining the second Essence of Nature, the Gift of Time, in Snake's Remains. After dancing successfully several times after winning the Boomerang, Link will receive the Strange Flute. However, Link must win the Strange Flute before he meets Ricky in Holodrum Plain.
Once Link reaches Spool Swamp with the help from Ricky, he will encounter Dimitri being attacked by the Great Moblin's henchmen. The henchmen will sell Dimitri to Link for 50 Rupees. Once Link pays the 50 Rupees, the henchmen will add another 30 Rupees to the price, thus requiring at least 80 Rupees to buy Dimitri. Once Link pays the 80 Rupees, the henchmen will leave Dimitri alone.
Dimitri will then thank Link and will help him in his quest to save the Oracle of Seasons by giving him his flute, making the Strange Flute become Dimitri's Flute and becoming Link's partner. If Link fails to obtain the Strange flute before going to Holodrum Plain, or he obtains the strange flute by means other than the Subrosian Dance Hall, he will be unable to be paired with Dimitri.
An early sign that Dimitri's Flute will be received is if the Natzu region takes on a river-style terrain with waterfalls and strong currents.
Oracle of Ages
In order for Link to obtain Dimitri's Flute, Link must buy the Strange Flute from the Lynna City Shop for 150 Rupees after gaining the third Essence of Time, the Echoing Howl, from the Moonlit Grotto. However, Link should buy the Strange Flute before going to the Nuun Highlands that are located north of Lynna City.
Once Link has checked the broken bridge that is recently being built, the Prankster Fairies will ask Link to help them find an animal that has recently gotten lost in their woods while playing hide 'n' seek with them. When Link finds the lost animal, it will turn out to be Dimitri.
Dimitri will thank Link for finding him and will help Link in his quest to save the Oracle of Ages by giving him his flute, making the Strange Flute become Dimitri's Flute and becoming Link's partner. However, if Link doesn't obtain the Strange Flute before going to the Nuun Highlands, or obtains the Strange flute by means other than the Lynna City Shop, he will be unable to be paired with Dimitri.
An early sign that Dimitri's Flute will be received is if the Nuun Highlands takes on a river-style terrain with waterfalls and strong currents.