Cast Brightstone Ritual from your graveyard for its escape cost by paying {R} and exiling three other cards from your graveyard, adding at least {R}{R}{R}{R}.
Activate Ambassador Laquatus by paying {3}, causing you to mill three cards.
Repeat.

Infinite self-mill

Underworld Breach

Brightstone Ritual

Ambassador Laquatus

Activate Elite Arcanist's ability by paying {1} and tapping it, casting a copy of Brightstone Ritual without paying its mana cost.
Resolve Brightstone Ritual, adding at least {2}.
Activate Pemmin's Aura's first ability by paying {1}, untapping Elite Arcanist.
Repeat.
If you control three or more Goblins, this combo nets infinite mana.

Infinite colored mana

Infinite magecraft triggers

Infinite storm count

Elite Arcanist

Mycosynth Lattice

Pemmin's Aura

Activate Elite Arcanist's ability by paying {1} and tapping it, casting a copy of Brightstone Ritual without paying its mana cost.
Resolve Brightstone Ritual, adding at least {2}.
Activate Freed from the Real's second ability by paying {1}, untapping Elite Arcanist.
Repeat.
If you control three of more Goblins, this combo nets infinite mana.

Freed from the Real

Chromatic Orrery

Combos with "Brightstone Ritual"