Hatchery Sliver + Shield Sphere + Leyline of Transformation

Hatchery Sliver

Shield Sphere

Leyline of Transformation

How it works

1. Cast Shield Sphere by paying 0, and choosing to pay its replicate cost an arbitrarily large number of times by paying 0.
2. Shield Sphere triggers, creating a copy of it for each time its replicate cost was paid.
3. Resolve all Shield Sphere spells, causing the nontoken Shield Sphere to enter the battlefield, and creating a token copy of it for each time its replicate cost was paid.

This dizzying combination relies on Leyline of Transformation to paint every creature you own—including artifacts like Shield Sphere—with the Sliver subtype, which in turn grants them all Hatchery Sliver's replicate ability. Because Shield Sphere has a mana value of zero, you can pay its replicate cost {0} an arbitrarily large number of times when casting it from your hand. This floods the battlefield with an endless stream of Shield Sphere tokens, instantly generating infinite creature enters-the-battlefield triggers and tokens for zero mana.