Esix, Fractal Bloom + Timestream Navigator + Endless Ranks of the Dead

Esix, Fractal Bloom

Timestream Navigator

Endless Ranks of the Dead

How it works

1. At the beginning of your upkeep, Endless Ranks of the Dead triggers, creating X copies of Timestream Navigator, where X is half the number of Zombies you control, rounded down.
2. Activate the oldest Timestream Navigator, paying 2 and putting Timestream Navigator on the bottom of your library to take an extra turn after this one.
3. Pass the turn.
4. Repeat.