The win-con is nobody knows how to resolve the gamestate anymore and you all agree to a new game.
Do your very best to convince your friends you're not going to drop gigantic eldrazi on them with Jhoira and set up some ramp/protection. Then, put as many miserable chaos effects into play as possible until everyone either succumbs to zany madness, or decides on a new game.
Omen Machine is not a "may" effect. Players must cast the spells they find with it. Even into an Eye of the Storm.
Once Scrambleverse starts to resolve, no player may respond until it has finished resolving.
Teferi's Puzzle Box + Omen Machine will empty everyone's hands.
Copying a Spell does not count as casting it. Keep note of this if you've got Hive Mind and Eye of the Storm in play at the same time.
If your table doesn't run much interaction, make sure you're all cool for a game that could take 3+ hours. I've experienced this multiple times playing this deck.
Why Karaoke Party? I got a fortune from a fortune cookie once that says "You will soon be invited to a karaoke party." on it, and I put it in the sleeve with Jhoira because I found it funny at the time. Still haven't been invited to a karaoke party, a decade+ running. One day...