Cast Echo of Eons by paying {4}{U}{U}, causing each player to discard their hands and draw seven cards.
Nekusar triggers for each card your opponents draw.
Resolve the first trigger, causing the opponent to get a poison counter.
If the opponent has ten or more poison counters, they lose the game as a state-based action.
Repeat from step 3 for each remaining trigger.
If needed, cast Echo of Eons from your graveyard for its flashback cost by paying {2}{U}, causing each player to discard their hands and draw seven cards.
Repeat from step 2.

Each opponent loses the game

Nekusar, the Mindrazer

Echo of Eons

Phyresis

Cast Echo of Eons by paying {4}{U}{U}, causing each player to discard their hands and draw seven cards.
Razorkin Needlehead triggers for each card your opponents draw.
Resolve the first trigger, causing the opponent to get a poison counter.
If the opponent has ten or more poison counters, they lose the game as a state-based action.
Repeat from step 3 for each remaining trigger.
If needed, cast Echo of Eons from your graveyard for its flashback cost by paying {2}{U}, causing each player to discard their hands and draw seven cards.
Repeat from step 2.

Razorkin Needlehead

Cast Echo of Eons by paying {4}{U}{U}, causing each player to shuffle their hand and graveyard into their library and draw seven cards.
Fate Unraveler triggers for each card your opponent draw this way, giving each opponent seven poison counters.
Cast Echo of Eons from your graveyard for its flashback cost by paying {2}{U}, causing each player to shuffle their hand and graveyard into their library, draw seven cards, and exile Echo of Eons.
Fate Unraveler triggers for each card your opponent draw this way, giving each opponent seven poison counters.
Each opponent loses the game due to having ten or more poison counters.

Fate Unraveler

Cast Echo of Eons by paying {4}{U}{U}, causing each player to shuffle their hand and graveyard into their library and draw seven cards.
Kederekt Parasite triggers for each card your opponent draw this way, giving each opponent seven poison counters.
Cast Echo of Eons from your graveyard for its flashback cost by paying {2}{U}, causing each player to shuffle their hand and graveyard into their library, draw seven cards, and exile Echo of Eons.
Kederekt Parasite triggers for each card your opponent draw this way, giving each opponent seven poison counters.
Each opponent loses the game due to having ten or more poison counters.

Kederekt Parasite

Cast Tainted Strike by paying {B}, giving Fate Unraveler +1/+0 and infect until end of turn.
Cast Echo of Eons by paying {4}{U}{U}, causing each player to shuffle their hand and graveyard into their library and draw seven cards.
Fate Unraveler triggers for each card your opponent draw this way, giving each opponent seven poison counters.
Cast Echo of Eons from your graveyard for its flashback cost by paying {2}{U}, causing each player to shuffle their hand and graveyard into their library, draw seven cards, and exile Echo of Eons.
Fate Unraveler triggers for each card your opponent draw this way, giving each opponent seven poison counters.
Each opponent loses the game due to having ten or more poison counters.

Tainted Strike

Cast Tainted Strike by paying {B}, giving Kederekt Parasite +1/+0 and infect until end of turn.
Cast Echo of Eons by paying {4}{U}{U}, causing each player to shuffle their hand and graveyard into their library and draw seven cards.
Kederekt Parasite triggers for each card your opponent draw this way, giving each opponent seven poison counters.
Cast Echo of Eons from your graveyard for its flashback cost by paying {2}{U}, causing each player to shuffle their hand and graveyard into their library, draw seven cards, and exile Echo of Eons.
Kederekt Parasite triggers for each card your opponent draw this way, giving each opponent seven poison counters.
Each opponent loses the game due to having ten or more poison counters.

Grafted Exoskeleton

Glistening Oil

Corrupted Conscience

Cast Walk the Aeons by paying its mana cost, causing you to take an extra turn after this one.
Move to your next turn. At the beginning of your precombat main phase, Echocasting Symposium's paradigm ability triggers, causing you to cast a copy of it from exile. 
Resolve the copy, creating a token copy of Scholar of the Ages
When the Scholar of the Ages token enters, it triggers, returning Walk the Aeons from your graveyard to your hand.
Repeat.

Infinite turns

Lock

Echocasting Symposium

Scholar of the Ages

Walk the Aeons

Cast Walk the Aeons by paying its mana cost.
Thor's second ability triggers, dealing damage to any target.
Resolve Walk the Aeons, causing you to take an extra turn after this one
Blink Thor using Abuelo.
When Thor enters, it triggers, exiling Walk the Aeons from your graveyard and allowing you to cast it from exile until the end of your next turn.
Move to your next turn.
Cast Walk the Aeons from exile by paying its mana cost.
Repeat from step 2.

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