How can you create a combo with Preston, the Vanisher, Karmic Guide, Glasspool Mimic // Glasspool Shore?
user
[START OF COMBO]This combo can be formed with Preston, the Vanisher, Karmic Guide, Glasspool Mimic // Glasspool Shore

Color identity: WU
Mana cost: {3}{W}{W}
Steps:
  1. Cast Karmic Guide by paying {3}{W}{W}.
  2. When Karmic Guide enters the battlefield, it triggers, returning Glasspool Mimic to the battlefield from your graveyard.
  3. Choose not to have Glasspool Mimic copy anything as it enters the battlefield.
  4. Glasspool Mimic dies as a state-based action due to having zero toughness.
  5. Preston triggers, creating a copy of Glasspool Mimic that is a 0/1 Illusion.
  6. Choose to have the Glasspool Mimic token enter the battlefield as a copy of Karmic Guide.
  7. When the Glasspool Mimic token enters the battlefield, it triggers, returning the nontoken Glasspool Mimic to the battlefield from your graveyard.
  8. Repeat from step 3.[END OF COMBO STEPS]

Result:
  - Infinite creature tokens
  - Infinite death triggers
  - Infinite enters the battlefield
  - Infinite leaves the battlefield[END OF COMBO RESULT][END OF COMBO]

Other prerequisites:
  - Preston, the Vanisher must be on the battlefield
  - Karmic Guide must be in your hand
  - Glasspool Mimic // Glasspool Shore must be in the graveyard
[END OF COMBO PREREQUISITES]
assistant