Yedora, Grave Gardener, Phyrexian Altar, and Scornful Egotist

Prerequisites

• Yedora, Grave Gardener on the battlefield
• Phyrexian Altar on the battlefield
• Scornful Egotist on the battlefield

Steps

1. Activate Phyrexian Altar by sacrificing Scornful Egotist, adding
2. When Scornful Egotist dies, Yedora triggers, returning Scornful Egotist from your graveyard to the battlefield face down as a Forest land
3. Activate Scornful Egotist by tapping it, adding
4. Activate Scornful Egotist's morph ability by paying , turning it face up
5. Repeat

Results

• Infinite death triggers
• Infinite green mana
• Infinite landfall triggers
• Infinite LTB
• Infinite sacrifice triggers