Yedora, Grave Gardener + Phyrexian Altar + Horde Ambusher

Yedora, Grave Gardener

Phyrexian Altar

Horde Ambusher

How it works

1. Activate Phyrexian Altar by sacrificing Horde Ambusher, adding one mana of any color.
2. When Horde Ambusher dies, Yedora triggers, returning Horde Ambusher from your graveyard to the battlefield face down as a Forest land.
3. Activate Horde Ambusher's morph ability by revealing a red card from your hand, turning it face up.
4. Repeat.

This clever loop relies on Yedora, Grave Gardener transforming your graveyard recursive cycle into a steady stream of landfalls by quietly catching your fallen creatures and returning them to the battlefield as face-down Forests. Once Horde Ambusher is safely back on the board in its arboreal disguise, you can immediately exploit its morph ability to turn it face up, clearing the way for the next iteration. Feeding that newly unmasked creature right back into Phyrexian Altar lets you sacrifice it to generate an unending supply of colored mana. Because Horde Ambusher's morph cost doesn't require actual mana, you only need to reveal a red card from your hand to flip it back up, keeping the entire machinery running infinitely.