Cast Expedition Envoy by paying {W/P}.
Defiler of Faith triggers, creating a 1/1 Soldier creature token.
Whenever Expedition Envoy enters the battlefield, it and Ondu Cleric trigger.
Resolve the Expedition Envoy trigger, putting a +1/+1 counter on it.
Resolve the Ondu Cleric trigger, causing you to gain at least two life.
Activate Phyrexian Altar by sacrificing the Soldier token, adding {W}.
Activate Sword of the Realms by paying {1}{W}, attaching it to Expedition Envoy.
Activate Phyrexian Altar by sacrificing Expedition Envoy, adding {1}.
When Expedition Envoy dies, Sword of the Realms triggers, returning Expedition Envoy from your graveyard to your hand.
Repeat.

Infinite death triggers

Infinite creature ETB

Infinite lifegain triggers

Infinite creature LTB

Infinite creature sacrifice triggers

Infinite storm count

Halvar, God of Battle // Sword of the Realms

Defiler of Faith

Phyrexian Altar

Ondu Cleric

Expedition Envoy

Cast Expedition Envoy by paying {W/P}.
Defiler of Faith triggers, creating a 1/1 Soldier creature token.
Whenever Expedition Envoy enters the battlefield, it and Ondu Cleric triggers, causing you to gain at least two life.
Activate Phyrexian Altar twice by sacrificing Expedition Envoy and the Soldier token, adding {1}{W}.
Whenever Expedition Envoy dies, Sigil of the New Dawn triggers, causing you to pay {1}{W} to return Expedition Envoy from your graveyard to your hand.
Repeat.

Sigil of the New Dawn

Combos with "Expedition Envoy"