Teferi's Convocation

Tap a Teferi Planeswalker you control: Search
target player's library for {x} number of Planeswalkers named Teferi, and put them onto
the battlefield under your control. Shuffle
afterwards. Exile Teferi's Convocation.
"I am the inception, the culmination, and the
resolution to all things, in all worlds, at all times.
I am Time itself."
- Teferi, Time Lord of the Multiverse