When Sparring Mummy enters, it triggers, untapping Emry.
Activate Lotus Petal by tapping and sacrificing it.
Repeat.
This loop transforms a graveyard and a handful of cheap permanents into an infinite engine, fueled entirely by the mana-generating sacrifice of Lotus Petal. **Emry, Lurker of the Loch** serves as your recursive engine, tapping to pull that exact Lotus Petal right back out of the graveyard every single iteration. Meanwhile, **Displacer Kitten** watches your back, triggering off the casting of the zero-mana artifact to blink **Sparring Mummy**. As Sparring Mummy re-enters the battlefield, its triggered ability untaps Emry so the whole process can begin anew.