Altaïr Ibn-La'Ahad, Éomer, Marshal of Rohan, Phyrexian Altar, and Leyline of Transformation

Prerequisites

• Altaïr Ibn-La'Ahad on the battlefield
• Éomer, Marshal of Rohan in the graveyard
• Phyrexian Altar on the battlefield
• Leyline of Transformation on the battlefield
• Altaïr does not have summoning sickness
• An opponent cannot block and kill Altaïr
• You have at least one legendary creature card exiled with a memory counter on it
• Leyline of Transformation on the battlefield with "Assassin" chosen

Steps

1. Declare Altaïr as an attacker
2. Altaïr triggers, exiling Éomer from your graveyard with a memory counter on it, and then creating a tapped and attacking token copy of each card you own that is exiled with a memory counter on it
3. Activate Phyrexian Altar by sacrificing another legendary creature token except Éomer, adding one mana of any color
4. When the creature dies, Éomer triggers, untapping all creatures you control and causing you to get an additional combat phase after this one
5. Repeat during each combat phase

Results

• Infinite LTB
• Infinite ETB
• Infinite colored mana
• Infinite sacrifice triggers
• Infinite death triggers
• Infinite combat phases