Activate Clone using Civilized Scholar's ability by tapping it.
Resolve that ability and choose to modify it with dredge, causing you to mill at least one card, return the creature card with dredge from your graveyard to your hand, then discard that same card, untap Clone and fail to transform it.
Repeat.

Infinite self-mill

Near-infinite self-discard triggers

Creature with dredge

Civilized Scholar // Homicidal Brute

Clone

Activate Mirror Image using Civilized Scholar's ability by tapping it.
Resolve that ability and choose to modify it with dredge, causing you to mill at least one card, return the creature card with dredge from your graveyard to your hand, then discard that same card, untap Mirror Image and fail to transform it.
Repeat.

Mirror Image

Cast Glasspool Mimic by paying {2}{U}. Choose to have it enter as a copy of Grub, Storied Matriarch.
Put Grub, Storied Matriach into your graveyard due to the legend rule.
When Glasspool Mimic enters, it triggers, returning Grub, Storied Matriarch from your graveyard to your hand.
Activate Agatha's Soul Cauldron by tapping it and exiling Civilized Scholar from your graveyard, putting a +1/+1 counter on Glasspool Mimic.
Activate Glasspool Mimic using Civilized Scholar's ability by tapping it, causing you to draw a card and discard Grub, Storied Matriarch. Glasspool Mimic will then untap itself and transform, but it will transform again into Grub, Storied Matriarch.
Glasspool Mimic triggers, returning Grub, Storied Matriarch from your graveyard to your hand.
Repeat from step 5.

Infinite card draw

Infinite draw triggers

Infinite self-discard triggers

Grub, Storied Matriarch // Grub, Notorious Auntie

Glasspool Mimic // Glasspool Shore

Agatha's Soul Cauldron

Cast Mirrorhall Mimic by paying {3}{U}. Choose to have it enter as a copy of Grub, Storied Matriarch.
Put Grub, Storied Matriach into your graveyard due to the legend rule.
When Mirrorhall Mimic enters, it triggers, returning Grub, Storied Matriarch from your graveyard to your hand.
Activate Agatha's Soul Cauldron by tapping it and exiling Civilized Scholar from your graveyard, putting a +1/+1 counter on Mirrorhall Mimic.
Activate Mirrorhall Mimic using Civilized Scholar's ability by tapping it, causing you to draw a card and discard Grub, Storied Matriarch. Mirrorhall Mimic will then untap itself and transform, but it will transform again into Grub, Storied Matriarch.
Mirrorhall Mimic triggers, returning Grub, Storied Matriarch from your graveyard to your hand.
Repeat from step 5.

Combos with "Civilized Scholar // Homicidal Brute"