Depends how much effort has SE put into making lamps random. It might be truly random with game performing 5-sided dice rolls every time you enter a lamp floor (or even not until someone clicks a lamp). It wouldn’t require that much computational power, especially after everyone who could/would use dats, got their 15/15 already and people who struggled/were late to the party will give up eventually – so not much extra server load.
If it’s quasi-random, it could be several ‘sets’ of numbers (If I’m not wrong, 3-lamp order has 6 possible permutations, 4-lamp: 24 permutations and 5-lamp: 120 permutations?), as someone suggested before, picked based on current floor number, current floor layout, current floor map used, current game day, game day you entered the zone, current moon %, party leader’s name, current weather in Tokyo etc. Pick three factors from the above, pop those into semi-randomizer equation and you’d have people having a very hard time figuring it out (given small sample sizes and most of the cheat-inclined people being done with the event by now).
On a bright side, it would be hilarious if the correct order was being sent into our client and stored in RAM.
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