Sun Titan, Phyrexian Altar, and Necrogen Communion

Prerequisites

• Sun Titan on the battlefield
• Phyrexian Altar on the battlefield
• Necrogen Communion on the battlefield

Steps

1. Activate Phyrexian Altar by sacrificing Sun Titan
2. When Sun Titan dies, Necrogen Communion triggers, returning Sun Titan from your graveyard to the battlefield
3. When Sun Titan enters, it triggers, returning Necrogen Communion from your graveyard to the battlefield attached to Sun Titan
4. Repeat

Results

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