Jegantha, the Wellspring + Horde of Notions + Goblin Bombardment + Rising of the Day

Jegantha, the Wellspring

Horde of Notions

Goblin Bombardment

Rising of the Day

How it works

1. Activate Jegantha by tapping it, adding that cannot be spent to pay generic mana costs.
2. Activate Goblin Bombardment 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 clever loop turns Jegantha, the Wellspring into a self-sacrificing mana source by tapping it for the exact five-color requirement needed to activate Horde of Notions. Because Jegantha has just been sent to the graveyard, Horde of Notions can pull it right back onto the battlefield for free, bypassing any need for generic mana (which Jegantha's restriction forbids anyway). Meanwhile, Goblin Bombardment provides the necessary outlet to bin Jegantha on command while converting each iteration into direct damage, and Rising of the Day ensures that Jegantha (and any other legendary creatures you control) retain immediate haste to keep the cycle spinning instantly.