Basalt Monolith + Biomancer's Familiar + Xenic Poltergeist

Basalt Monolith

Biomancer's Familiar

Xenic Poltergeist

How it works

1. Activate Xenic Poltergeist by tapping it, causing Basalt Monolith to become an artifact creature until end of turn.
2. Activate Basalt Monolith's first ability by tapping it, adding CCC.
3. Activate Basalt Monolith's last ability by paying 1, untapping it.
4. Repeat from step 2.

By bringing Xenic Poltergeist to life, you turn Basalt Monolith from an ordinary rock into an artifact creature with a mana value of three. This transformation is the clever secret to the engine, because it allows Biomancer's Familiar to step in and reduce the cost of Basalt Monolith's untap ability from three mana down to just one. With that discount in place, tapping Basalt Monolith for three colorless mana easily pays for the single-mana untap cost while netting a positive return. The result is a seamless loop that endlessly generates infinite colorless mana to fuel the rest of your Commander, Legacy, Oathbreaker, or Vintage strategy.