How can you create a combo with Prototype Portal, Ugin's Nexus, Krark-Clan Ironworks?
user
[START OF COMBO]This combo can be formed with Prototype Portal, Ugin's Nexus, Krark-Clan Ironworks

Color identity: C
Mana cost: {5} each turn
Steps:
  1. Activate Prototype Portal by paying {5} and tapping it, creating a token copy of Ugin's Nexus.
  2. Activate Krark-Clan Ironworks by sacrificing the Ugin's Nexus token, adding {C}{C}.
  3. The Ugin's Nexus token is exiled instead of being put into your graveyard, causing you to take an extra turn after this one.
  4. Repeat each turn.[END OF COMBO STEPS]

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

Other prerequisites:
  - Prototype Portal must be on the battlefield
  - Ugin's Nexus must be exiled
  - Krark-Clan Ironworks must be on the battlefield
[END OF COMBO PREREQUISITES]
assistant