How can you create a combo with Karn, the Great Creator, Ugin's Nexus, Throne of Geth, Inexorable Tide?
user
[START OF COMBO]This combo can be formed with Karn, the Great Creator, Ugin's Nexus, Throne of Geth, Inexorable Tide

Color identity: U
Mana cost: {5} each extra turn
Steps:
  1. Activate Throne of Geth by tapping it and sacrificing Ugin's Nexus.
  2. Ugin's Nexus is exiled instead of being put into your graveyard, causing you to take an extra turn after this one.
  3. Resolve the Throne of Geth ability, putting a loyalty counter on Karn.
  4. Activate Karn's second loyalty ability by removing two loyalty counters from it, returning Ugin's Nexus from exile to your hand.
  5. Move to your next turn.
  6. Cast Ugin's Nexus by paying {5}.
  7. Inexorable Tide triggers, putting a loyalty counter on Karn.
  8. Repeat.[END OF COMBO STEPS]

Result:
  - Infinite turns[END OF COMBO RESULT][END OF COMBO]

Other prerequisites:
  - All permanants must be on the battlefield
  - Karn has at least two loyalty counters on it.
[END OF COMBO PREREQUISITES]
assistant