Resolve Pact of the Titan, creating a 4/4 Giant creature token.
Repeat an arbitrarily large number of times.
Deal combat damage to each opponent using the Giants, causing them to lose the game due to having zero or less life.
This crafty setup revolves around Elite Arcanist, which starts the engine by exiling Pact of the Titan and repeatedly casting copies of it for zero mana thanks to its activated ability. Every time you cast one of those spells, Chakram Retriever's triggered ability steps in to untap Elite Arcanist, allowing you to repeat the process infinitely to flood the board with 4/4 Giant tokens. Meanwhile, Brudiclad, Telchor Engineer ensures those newly minted Giants are immediately lethal by granting your entire army haste right out of the gate.