Jedit Ojanen, Mercenary, Leyline of Singularity, and Phyrexian Altar

Prerequisites

• Jedit Ojanen, Mercenary on the battlefield
• Leyline of Singularity on the battlefield
• Phyrexian Altar on the battlefield

Steps

1. Cause a creature to enter the battlefield under your control, which will be legendary due to Leyline of Singularity
2. Jedit triggers, causing you to pay to create a 2/2 Cat Warrior creature token that is legendary due to Leyline of Singularity
3. The Cat Warrior enters the battlefield, triggering Jedit
4. Holding priority, activate Phyrexian Altar by sacrificing the Cat Warrior, adding
5. Resolve the Jedit trigger, causing you to pay to create a 2/2 Cat Warrior creature token that is legendary due to Leyline of Singularity
6. Repeat from step 3

Results

• Infinite death triggers
• Infinite creature ETB
• Infinite creature LTB
• Infinite creature sacrifice triggers