Activate Isochron Scepter by paying {2} and tapping it, casting a copy of Pull from Eternity without paying its mana cost.
Resolve the copy of Pull from Eternity, putting Draco into your graveyard from exile.
Activate Academy Ruins' second ability by paying {1}{U} and tapping it, putting Draco on top of your library from your graveyard.
Move to the next turn.
At the beginning of that turn's upkeep, Timesifter triggers, exiling the top card of each player's library, and causing you to take an extra turn after this one due to exiling the highest mana value card.
Repeat.

Infinite turns

Lock

Timesifter

Draco

Isochron Scepter

Pull from Eternity

Academy Ruins

Declare Varragoth as an attacker.
Activate Varragoth by paying {1}{B}, searching your library for Draco, then shuffling your library and putting Draco on top of it.
During the next upkeep, Timesifter triggers, exiling Draco and causing you to get an extra turn after this one.
Activate Emiel by paying {3}, blinking Riftsweeper.
Riftsweeper enters the battlefield, shuffling Draco from exile into your library.
Repeat.

Varragoth, Bloodsky Sire

Emiel the Blessed

Riftsweeper

Declare Varragoth as an attacker.
Activate Varragoth by paying {1}{B}, searching your library for Draco, then shuffling your library and putting Draco on top of it.
During the next upkeep, Timesifter triggers, exiling Draco and causing you to get an extra turn after this one.
Activate Eldrazi Displacer by paying {2}{C}, blinking Riftsweeper.
Riftsweeper enters the battlefield, shuffling Draco from exile into your library.
Repeat.

Combos with "Timesifter"