Here is a new, even more crazy list, that kills every opponent (3) in a different way: Mill, Damage and Game Lost.
Passively: Akroma's Memorial gives Haste, Teferi protects all, Kongming gives +1/+1 to all our creatures.
Step 0) Enter the Battlefields: Sharuum brings Strionic Resonator into play, Gonti's Aether Heart gives way enough energy to be sac'ed. Titania grabs Crystal Quarry for fixing.
Step 1) Nissa untaps 4 lands, Teferi 4 more, tap Nykthos on blue devotion. (7 mana available +9 blue)
Step 2) Hanna targets Followed Footstep, then strionic resonator on Paradox Haze. (6 mana + 5 blue)
Step 3) Memory's Journey, returning unimportant card, Mind Grind, Time Sieve on the bottom of the empty library. (5 mana available + 5 blue)
Step 4) Play Paradox Haze on yourself, using the floating blue.
Step 5) Pass to combat (wasting 1 blue), attacking with Alesha, trigger on Clever Impersonator. Refuse to target with Clever Impersonator. It survives due to Kongming making it a 1/1.
Step 6) Second main phase, spend all 5 remaining mana on Followed Footsteps, targetting Clever Impersonator.
Step 7) Vivien Reid kills the Ugin's Nexus, giving you an extra turn. Pass to extra turn.
Step 8) Upkeeps, paradox haze gives us a second upkeep. Each upkeep, Clever Impersonator is copied, transforming into Paradox Haze on entry. (3 Paradox Hazes in play) Red Honden pings one player for 8. (4 Shrines in play)
Step 9) Using Garruk to untap Crystal Quarry and Nykthos a second time, pay WWUUBBRRGG for Door to Nothingness, killing one player. (2 left)
Step 10) Crack Gonti's Aether Heart for another extra turn.
Step 11) Upkeeps (4), same target, make 4 new Paradox Haze, dome the same player for 16 damage (24 total from the shrines).
Step 12) If you haven't drawn Time Sieve, use Teferi to grab it (first ability) then use Krosan Reclamation on random cards to avoid decking.
Step 13) Play Time Sieve, sac Breya, her two thopters, Sharuum and Strionic resonator to the Sieve, extra turn.
Step 14) Next turn, Upkeeps, create tokens of the Red Honden to deal a grand total of 64 damage to one player's face since the combo started.
Step 15) If the previous step didn't force you to kill two players, use all your Nykthos mana to Mind Grind the remaining player to dust (for around 60 lands.)
Congrats, you just wasted an hour of everyone's time, killed someone with damage, shown someone the door and ground a third person's mind to dust.