Delina, Wild Mage + Port Razer

Delina, Wild Mage
Port Razer

Requires
All permanents on the battlefield. Delina does not have summoning sickness. An opponent is unable to block and kill creatures you control.
Steps
  1. Declare Delina as an attacker, attacking any opponent unable to block and kill your creatures
  2. Delina triggers, creating at least one token copy of Port Razer that is tapped and attacking
  3. Deal combat damage with the Port Razer token
  4. The Port Razer token triggers, causing you to untap all creatures you control and to get an additional combat phase after this one
  5. At the end of the combat phase, the Port Razer token triggers, exiling itself
  6. Repeat
Results
Infinite combat phases. Infinite combat damage. Infinite ETB. Infinite LTB. Infinite untap of creatures you control.