Cast Glasspool Mimic by paying {0} due to Aluren, choosing to have it enter the battlefield as a copy of Mischievous Pup.
When Glasspool Mimic enters the battlefield, it triggers, returning Mischievous Pup from the battlefield to your hand.
Cast Mischievous Pup by paying {0} due to Aluren.
When Mischievous Pup enters the battlefield, it triggers, returning Glasspool Mimic from the battlefield to your hand.
Repeat.

Infinite creature ETB

Infinite creature LTB

Infinite storm count

Aluren

Mischievous Pup

Glasspool Mimic // Glasspool Shore

Cast Mirror Image by paying {0} due to Aluren, choosing to have it enter the battlefield as a copy of Mischievous Pup.
When Mirror Image enters the battlefield, it triggers, returning Mischievous Pup from the battlefield to your hand.
Cast Mischievous Pup by paying {0} due to Aluren.
When Mischievous Pup enters the battlefield, it triggers, returning Mirror Image from the battlefield to your hand.
Repeat.

Mirror Image

Cast Flesh Duplicate by paying {0} due to Aluren, choosing to have it enter the battlefield as a copy of Mischievous Pup.
When Flesh Duplicate enters the battlefield, it triggers, returning Mischievous Pup from the battlefield to your hand.
Cast Mischievous Pup by paying {0} due to Aluren.
When Mischievous Pup enters the battlefield, it triggers, returning Flesh Duplicate from the battlefield to your hand.
Repeat.

Flesh Duplicate

Cast Phantasmal Image by paying {0} due to Aluren, choosing to have it enter the battlefield as a copy of Mischievous Pup.
When Phantasmal Image enters the battlefield, it triggers, returning Mischievous Pup from the battlefield to your hand.
Cast Mischievous Pup by paying {0} due to Aluren.
When Mischievous Pup enters the battlefield, it triggers, returning Phantasmal Image from the battlefield to your hand.
Repeat.

Combos with "Mischievous Pup"