Jegantha, the Wellspring + Horde of Notions + Phyrexian Altar + Samut, Voice of Dissent

Jegantha, the Wellspring

Horde of Notions

Phyrexian Altar

Samut, Voice of Dissent

How it works

1. Activate Jegantha by tapping it, adding that cannot be spent to pay generic mana costs.
2. Activate Phyrexian Altar by sacrificing Jegantha.
3. Activate Horde of Notions by paying , causing you to cast Jegantha from your graveyard without paying its mana cost.
4. Repeat.

This loop relies on Jegantha, the Wellspring being able to generate the exact WUBRG color combination needed to fuel Horde of Notions' activated ability, casting Jegantha straight back from the graveyard after it hits the bin. Phyrexian Altar provides the crucial sacrifice outlet that converts Jegantha into the exact colored mana required to activate the Horde, while its ability to accept colored mana neatly bypasses Jegantha's restriction against paying generic costs. Meanwhile, Samut, Voice of Dissent sits ready with haste and untap utility, though the core engine runs entirely on the endless recycling loop between the Altar, the Horde, and the Elk.