How can you create a combo with Yore-Tiller Nephilim, Port Razer, Phyrexian Altar?
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[START OF COMBO]This combo can be formed with Yore-Tiller Nephilim, Port Razer, Phyrexian Altar

Color identity: WUBR
Mana cost: 
Steps:
  1. Declare Yore-Tiller Nephilim as an attacker.
  2. Yore-Tiller Nephilim triggers, returning Port Razer from your graveyard onto the battlefield tapped and attacking.
  3. Deal combat damage with Port Razer and Yore-Tiller Nephilim.
  4. Port Razer triggers, untapping each creature you control and causing you to get an additional combat phase after this one.
  5. Activate Phyrexian Altar by sacrificing Port Razer, adding one mana of any color.
  6. Repeat each combat phase.[END OF COMBO STEPS]

Result:
  - Infinite combat damage
  - Infinite combat phases
  - Infinite death triggers
  - Infinite enters the battlefield
  - Infinite leaves the battlefield
  - Infinite mana creatures you control can produce
  - Infinite sacrifice triggers
  - Infinite untap of creatures you control[END OF COMBO RESULT][END OF COMBO]

Other prerequisites:
  - Yore-Tiller Nephilim must be on the battlefield
  - Port Razer must be in the graveyard
  - Phyrexian Altar must be on the battlefield
  - Yore-Tiller Nephilim does not have summoning sickness.
  - An opponent is unable to block creatures you control.
[END OF COMBO PREREQUISITES]
assistant