Urban Daggertooth + Pyrohemia + Pentad Prism

Urban Daggertooth

Pyrohemia

Pentad Prism

How it works

1. Activate Pyrohemia by paying , dealing 1 damage to each creature and each player.
2. Urban Daggertooth triggers, putting a +1/+1 counter on Urban Daggertooth and a charge counter on Pentad Prism.
3. Activate Pentad Prism's ability by removing a charge counter from it, adding .
4. Repeat.

This clever loop relies on Pyrohemia acting as a repeatable damage source that safely pings the board for a single red mana. Each time the damage hits, Urban Daggertooth's *enrage* ability triggers to proliferate, which conveniently replenishes the charge counter on Pentad Prism. You can then pull that charge counter right back off Pentad Prism to generate the red mana needed to activate Pyrohemia all over again.