Activate Staff of Domination by tapping it, adding two mana of any color and causing the next spell you cast this turn to have cascade.
Activate Staff of Domination's first ability by paying {1}, untapping it.
Repeat.
Once you have infinite mana, you may use it to activate Staff of Domination's other abilities.

Infinite card draw

Infinite cascade with mana value equal to the next spell you cast

Infinite colored mana

Infinite draw triggers

Infinite lifegain

Infinite lifegain triggers

Infinite mana creatures you control can produce

Infinite untap of creatures you control

Bigger on the Inside

Staff of Domination

Activate Pili-Pala by tapping it, adding {2} and causing the next spell you cast to have cascade.
Activate Pili-Pala by paying {2} and untapping it, adding one mana of any color.
Repeat.
Optionally, you may cast any spell to get infinite cascade triggers based off the mana value of that spell.

Pili-Pala

Activate the creature with Bigger on the Inside and Freed from the Real attached by tapping it, adding {U}{U} and causing the next spell you cast this turn to have cascade.
Activate Freed from the Real by paying {U}, untapping the creature.
Repeat.

Freed from the Real

Activate Farmstead Gleaner by tapping it, adding {2} and causing the next spell you cast to have cascade.
Activate Farmstead Gleaner by paying {2} and untapping it, putting a +1/+1 counter on it.
Repeat.
Optionally, you may cast any spell to get infinite cascade triggers based off the mana value of that spell.

Infinite +1/+1 counters on Farmstead Gleaner

Farmstead Gleaner

Activate Deserted Temple's second ability by paying {0} due to Blossoming Tortoise and tapping it, targeting itself.
Rings of Brighthearth triggers, causing you to pay {2} to copy Deserted Temple's ability, targeting Deserted Temple.
Resolve the copy of Deserted Temple's ability, untapping it.
Activate Deserted Temple by tapping it, adding two mana of any color and causing the next spell you cast this turn to have cascade.
Resolve the Deserted Temple ability from step 1, untapping it.
Repeat.
Cast any nonland card from your hand by paying its mana cost, causing you to get infinite cascade triggers based off the mana value of that spell.

Blossoming Tortoise

Deserted Temple

Rings of Brighthearth

Activate Retrofitter Foundry by tapping it, adding two mana of any color and causing the next spell you cast this turn to have cascade.
Activate Retrofitter Foundry's first ability by paying {1}, untapping it.
Repeat.
Once you have infinite mana, you may activate Retrofitter Foundry's other abilities.

Combos with "Bigger on the Inside"