Cast Soultether Golem by paying {2}.
Soultether Golem enters the battlefield with a time counter on it due to its vanishing ability.
Kate Stewart's first ability triggers, creating a 1/1 Soldier creature token.
When the Soldier enters the battlefield, Soultether Golem's second ability triggers, putting a time counter on it.
Repeat from step 3.
NOTE: This combo creates a mandatory infinite loop that ends the game in a draw if it isn't interacted with.

Draw the game

Infinite creature tokens

Infinite creature ETB

Kate Stewart

Soultether Golem

Activate Jhoira's Timebug by tapping it, putting a time counter on a permanent you control that already has a time counter on it.
Kate's first ability triggers, creating a 1/1 Soldier creature token.
When the Soldier enters, Intruder Alarm triggers, untapping all creatures.
Repeat.

Infinite mana creatures you control can produce

Infinite untap of creatures

Intruder Alarm

Jhoira's Timebug

Activate Hourglass of the Lost's first ability by tapping it, adding {W} and putting a time counter on it.
Kate's first ability triggers, creating a 1/1 Soldier creature token.
When the Soldier enters, Intruder Alarm triggers, untapping all creatures.
Activate Aphetto Alchemist by tapping it, untapping Hourglass of the Lost.
Repeat.

Infinite white mana

Infinitely large creatures you control until end of turn

Hourglass of the Lost

Aphetto Alchemist

Animate Hourglass of the Lost using Mind Transfer Protocol.
Activate Hourglass of the Lost's first ability by tapping it, adding {W} and putting a time counter on it.
Kate's first ability triggers, creating a 1/1 Soldier creature token.
When the Soldier enters, Intruder Alarm triggers, untapping all creatures.
Repeat from step 2.

Combos with "Kate Stewart"