Activate up to five lands by tapping them, adding at least {2}{U}{B}{B}.
Activate Tortured Existence by paying {B} and discarding Peregrine Drake, targeting any other creature card in your graveyard.
Hashaton triggers, causing you to pay {2}{U} to create a token copy of Peregrine Drake that is a 4/4 Zombie.
When the Peregrine Drake token enters the battlefield, it triggers, untapping up to five lands.
Resolve the Tortured Existence ability, returning the targeted creature from your graveyard to your hand.
Activate Tortured Existence by paying {B} and discarding a creature card, targeting Peregrine Drake.
Hashaton triggers. Choose not to pay.
Resolve the Tortured Existence ability, returning Peregrine Drake from your graveyard to your hand.
Repeat.

Infinite ETB

Infinite self-discard triggers

Infinite tapped creature tokens

Hashaton, Scarab's Fist

Tortured Existence

Peregrine Drake

Discard Sharuum in any way. Hashaton triggers, causing you to pay {2}{U} to create a token copy of Sharuum that is a 4/4 black Zombie.
When the Sharuum token enters the battlefield, it triggers, returning the nontoken Sharuum from your graveyard to the battlefield.
Put the nontoken Sharuum into your graveyard due to the legend rule.
The nontoken Sharuum's enter-the-battlefield ability triggers, returning it from your graveyard to the battlefield.
Repeat from step 3.

Infinite LTB

Infinite death triggers

Sharuum the Hegemon

Activate Gilded Lotus by tapping it, adding {U}{U}{U}.
Activate Mind Over Matter by discarding Graveshifter.
Hashaton triggers, causing you to pay {2}{U} to create a tapped token copy of Graveshifter that is a 4/4 Zombie.
When the Graveshifter token enters the battlefield, it triggers, returning Graveshifter from your graveyard to your hand.
Resolve the Mind Over Matter ability, untapping Gilded Lotus.
Repeat.

Mind Over Matter

Gilded Lotus

Graveshifter

Combos with "Hashaton, Scarab's Fist"