So, I have a theory as to why the Dune Rares are so… rare on certain days.
Today, I’ve noticed they’ve exclusively spawned right as General Zarathura or Garudeon died.
So my theory: They are tied to the other desert rares, Garudeon, Zarathura, and Akkaris.
And the reason they’re so rare on some days? Because Akkaris and Zarathura are in a rotation, and not always up. So some days, we only have Garudeon that can trigger their spawn.
Can people help me test this? Kill Garudeon, Zarathura, and Akkaris when they’re up - watch if their death triggers the Dunes. (It obviously isn’t a 100% spawn rate lol, but just keep an eye out). Also keep an eye out for Otaris, Phestis, and Hadeon, as those might also constitute desert rares.