At the beginning of your precombat main phase, The World Spell triggers, putting a lore counter on itself.
The World Spell's third chapter ability triggers, causing you to put Tom Bombadil onto the battlefield from your hand and sacrifice The World Spell.
Mortuary, Cloudstone Curio and Tom Bombadil each trigger.
Resolve the Mortuary trigger, putting The World Spell on top of your library from your graveyard.
Resolve the Cloudstone Curio trigger, choosing to return nothing to your hand from the battlefield.
Resolve the Tom Bombadil trigger, causing you to reveal The World Spell from the top of your library and put it onto the battlefield.
Choose to have The World Spell enter with three lore counters due to its read-ahead ability.
Cloudstone Curio and The World Spell's third chapter ability trigger.
Resolve the Cloudstone Curio trigger, returning Tom Bombadil to your hand from the battlefield.
Resolve the World Spell trigger, causing you to put Tom Bombadil onto the battlefield from your hand and sacrifice The World Spell.
Repeat from step 3.
If desired, you may return a creature card to your hand in step 5, which can then be returned in step 2 for infinite blinking of any creature(s).

Infinite blinking

Infinite death triggers

Infinite creature ETB

Infinite creature LTB

Infinite creature sacrifice triggers

Tom Bombadil

The World Spell

Mortuary

Cloudstone Curio

Starfield of Nyx

Opalescence

Combos with "Tom Bombadil"