You should be able to see this phenomena for a little while, about 2 or 3 weeks. If you are the first guy linking to a neighborhood, you'll get the most of the phenomena. After 5 or 10 minutes, it stops.
You have to give the hood a little break (few hours

I didn't test the time accurately...I only know that if you return to your neighborhood or any other neighborhood the next day, the 5 to 10 mins fireworks will restart)
Once it's over, you can force the fireworks to appears. It something best done with a party of 3.
Let me recall. There are 3 distincts fireworks.
1) The big fountain center one - to trigger it you have to run back-and-forth on the high balcony, the duration of the fireworks is about 1 min
2) The 2 small ones beside the banner - to trigger them you have to run on the classroom top on the section over the seed room door
3) The 2 small ones on community room balcony - to trigger them you have to jump over the small rock near the windows in the light garden where you can sometimes find a Relto page.
Maybe i'm mixing up the 2 last triggers. If so, it's the exact opposite. The trigger actions are the good ones maybe just what the effect triggered can be mixed up. It only happen twice a year (Occidental New Year & D'ni New Year)
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